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THE    FOUNDATIONS   OF  ZOOLOGY 

A   COURSE    OF   LECTURES 

DELIVERED   AT   COLUMBIA   UNIVERSITY 

ON   THE   PRINCIPLES   OF   SCIENCE 

AS  ILLUSTRATED  BY  ZOOLOGY 


Columfeia  3Eni&er0itg  ISiological  SSziits 

EDITED   BY 
HENRY    FAIRFIELD   OSBORN 

AND 

EDMUND    B.   WILSON 

I.  FROM   THE   GREEKS  TO   DARWIN 

By  Henry  Fairfield  Osborn 

II.  AMPHIOXUS  AND  THE  ANCESTRY  OF  THE  VERTEBRATES 

By  Arthur  Willey 

III.  FISHES,    LIVING  AND   FOSSIL.      An  Introductory  Study 

By  Bashford  Dean 

IV.  THE   CELL   IN   DEVELOPMENT  AND   INHERITANCE 

By  Edmund  B.  Wilson 

V.    THE   FOUNDATIONS  OF  ZOOLOGY 
By  W.  K.  Brooks 

VI.    THE   PROTOZOA 

By  Gary  N.  Calkins 

VII.     REGENERATION 

By  T.  H.   Morgan 

VIII.     THE    DYNAMICS   OF   LIVING   MATTER 
By  Jacques  Loeb 

IX.    ANTS:  THEIR  STRUCTURE,  DEVELOPMENT  AND  BEHAVIOR 

By  W.  M.  Wheeler 

X.     BEHAVIOR   OF  THE    LOWER   ORGANISMS. 
By  H.  S.  Jennings 


COLUMBIA    UNIVERSITY    PRESS 

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COLUMBIA     UNIVERSITY   BIOLOGICAL    SERIES.      V. 


THE 


FOUNDATIONS  OF  ZOOLOGY 


BY 


WILLIAM    KEITH    BROOKS,   Ph.D.,  LL.D. 

PROFESSOR   OF    ZOOLOGY    IN    THE   JOHNS    HOPKINS   UNIVERSITY 


SECOND    EDITION,    REVISED 


COLUMBIA  UNIVERSITY  PRESS 

1915 

All  rights  reserved 


Copyright,  1899, 

By  the  macmillan  company. 


Set  up  and  electrotyped.     Published  January,  1899. 
Reprinted  March,  1907;  November,  1915. 


Nortocot)  ^rtaa 
J.  8.  Gushing  &  Co.  —  Berwick  &  Smith  Co. 

Norwood,  Mass  ,  U  3.  A 


Zo  ^ofaart  College 


WHERE    I     LEARNED    TO    STUDY,    AND,    I    HOPE,    TO    PROFIT    BY 

BUT    NOT    TO    BLINDLY    FOLLOW,    THE   WRITINGS    OF    THAT 

GREAT  THINKER   ON   THE   PRINCIPLES  OF   SCIENCE 

GEORGE    BERKELEY 

I   HAVE,    BY   PERMISSION,    DEDICATED   THIS    BOOK 


CONTENTS 


LECTURE   I 

PAGE 

Introductory       3 

LECTURE  II 
Huxley,  and  the  Problem  of  the  Naturalist 33 

LECTURE   III 
Nature  and  Nurture 49 

LECTURE    IV 
Lamarck 83 

LECTURE   V 
Migration  in  its  bearing  on  Lamarckism loi 

LECTURE   VI  — Part  I 
Zoology,  and  the  Philosophy  of  Evolution 123 

LECTURE   VI— Part  II 
A  Note  on  the  Views  of  Galton  and  Weismann  on  Inheritance     .     143 

LECTURE   VII 
Galton,  and  the  Statistical  Study  of  Inheritance    .        .        .        -153 

LECTURE   VIII 
Darwin,  and  the  Origin  of  Species 183 

LECTURE    IX 
Natural  Selection,  and  the  Antiquity  of  Life 215 

vii 


viii  CONTENTS 

LECTURE    X 

PAGE 

Natural  Selection  and  Natural  Theology 241 

LECTURE   XI 
Paley,  and  the  Argument  from  Contrivance 269 

LECTURE  XII 
The  Mechanism  of  Nature 287 

LECTURE   XIII 
Louis  Agassiz  and  George  Berkeley 317 


LECTURE    I 


INTRODUCTORY 


"The  doctrine  of  idols  bears  the  same  relation  to  the  interpretation  of  nature  as  that  of 
sophisms  does  to  common  logic.  It  is  the  peculiar  and  perpetual  error  of  the  human  under- 
standing to  be  more  moved  and  excited  by  affirmations  than  by  negations;  whereas  it  ought 
duly  and  regularly  to  be  impartial;  nay,  in  establishing  any  true  axiom  the  negative  instance 
is  the  most  powerful."  —  Francis  Bacon. 


LECTURE  I 

INTRODUCTORY 

In  this  course  of  lectures  I  shall  give,  on  many  questions,  the 
Scotch  verdict  of  "  not  proven,"  and  experience  warns  us  that 
this  will  be  interpreted  as  an  assertion  that  they  are  proved  or 
disproved,  although  no  one  can,  in  justice,  interpret  an  admission 
that  a  thesis  may  some  time  be  proved  or  disproved  as  belief 
that  either  of  these  things  will  come  about,  or  as  an  admission 
of  anything  else  except  a  suspension  of  judgment,  for  all  must 
hold  it  the  height  of  folly  to  found  a  scientific  opinion  on  lack  of 
evidence. 

If  I  sometimes  speak  of  things  that  are  not  commonly  held  to 
fall  within  the  province  of  zoology,  —  if  I  try  now  and  then  for 
soundings  in  waters  which  able  pilots  tell  us  are  far  out  of  the  course 
of  our  ship,  —  I  hope  they  who  follow  me  to  the  end  of  our  voyage 
will  admit  that  I  have  not  wandered  from  our  true  course ;  although 
it  may  be  well  to  show  now,  by  way  of  introduction,  how  it  is  that 
zoologists  find  themselves  face  to  face  with  many  problems  which 
other  men  of  science  have  agreed  to  lay  aside  as  insoluble  or  irrele- 
vant. 

I  shall  try  to  show  that  life  is  response  to  the  order  of  nature  — 
in  fact,  this  thesis  is  the  text  of  most  of  the  lectures ;  but  if  it  be 
admitted,  it  follows  that  biology  is  the  study  of  response,  and  that 
the  study  of  that  order  of  nature  to  which  response  is  made  is  as 
well  within  its  province  as  the  study  of  the  living  organism  which 
responds,  for  all  the  knowledge  we  can  get  of  both  these  aspects 
of  nature  is  needed  as  a  preparation  for  the  study  of  that  relation 
between  them  which  constitutes  Hfe.  Our  interest  in  all  branches  of 
science  is  vital  interest.     It  is  only  as  living  things  that  we  care  to 

D.  H.  HILL  L!BRA!57 


North  Carolina  State  College 


4  THE  FOUNDATION'S  OF  ZOOLOGY 

know.  Life  is  that  which,  when  joined  to  mind,  is  knowledge, — 
knowledge  in  use ;  and  we  may  be  sure  that  all  living  things  with 
minds  like  ours  are  conscious  of  some  part  of  the  order  of  nature^ 
for  the  response  in  which  life  consists  is  response  to  this  order.  The 
statement  that  physical  phenomena  are  natural  seems  to  mean  little, 
but  the  phenomena  of  life  are  so  wonderful  that  many  hesitate,  even 
at  the  present  day,  to  believe  that  nature  can  be  such  a  wonderful 
thing  as  it  must  be  if  the  actions  of  all  living  things  are  natural ; 
and,  as  I  shall  try  to  find  out  in  this  course  of  lectures  what  we  mean 
by  the  assertion  that  living  nature  is  natural,  I  shall  now  attempt,  by 
a  few  illustrations,  to  give  a  broad  outline  of  some  of  the  most  nota- 
ble features  of  the  nature  of  living  things. 

The  outer  surface  or  shell  of  a  crab  is  an  excretion  that  is  formed 
once  for  all ;  for  while  it  may  stretch  a  little  at  the  joints,  it  does  not 
grow,  and  as  the  living  body  must  in  time  become  too  large  for  it, 
new  shells,  one  size  larger,  are  formed  from  time  to  time  under  the 
old  one,  which  is  then  thrown  off.  The  frequency  of  these  moultings 
conforms  to  the  rate  of  growth.  The  little  crab  sheds  its  shell  either 
before  or  a  few  minutes  after  it  is  hatched  from  the  ^^^,  and  a  second 
moulting  takes  place  within  forty-eight  hours,  but  the  next  interval 
lasts  four  or  five  days,  and  each  successive  shell  remains  useful  for  a 
longer  time,  until  a  mature  crab  m.ay  pass  a  year  or  even  longer  with- 
out moulting.  The  process  is  natural  or  mechanical,  for  nothing  the 
crab  can  do  for  itself  retards  or  hastens  its  growth  or  the  secretion 
of  a  new  shell ;  nor  can  any  part  of  the  process  be  attributed  to  its 
own  actions,  except  so  far  as  these  actions  are  due  to  its  nature, 
although  it  will  not  grow  unless  it  seeks  and  finds  food,  nor  will  the 
old  shell  take  itself  off,  unless  the  crab  draws  its  limbs  out  by  bodily 
movements  which  are  both  complex  and  violent. 

Many  enemies,  man  and  the  hard  crab  among  them,  prize  the  soft 
crab  as  a  palatable  delicacy,  and  as  it  is  helpless  and  defenceless 
while  moulting,  and  until  the  new  shell  has  grown  hard,  the  crab 
hides  under  the  sand  or  among  the  grass  of  the  marshes  until  the 
dangerous  crisis  is  past.  No  one  can  say  whether  the  crab  is  or  is 
not  conscious  of  its  danger,  or  whether  it  hides  voluntarily  or  involun- 
tarily, but  as  no  crab  which  has  not  escaped  its  enemies  at  the  moult- 
ing season  now  survives,  all  the  modern  edible  crabs  hide  by  nature, 
just  as  they  grow  and  shed  their  shells  by  nature.     Some  crabs  pass 


INTRODUCTORY  5 

most  of  their  lives  in  places  which  seem  to  have  been  sought,  at  first, 
for  shelter  during  the  moulting  period.  A  species  of  Porcellana 
clings  to  the  lower  surface  of  the  broad  shell  of  Limulus,  and  the 
Pinnixas  live  in  the  burrows  which  annelids  make  in  the  floor  of  the 
ocean.  I  have  found  a  species  of  Pinnixa  living  on  the  shoals  at 
Beaufort,  N.C.,  in  the  parchment-like  tubes  with  which  the  annelid 
Chaetopterus  lines  its  burrow,  and  as  the  opening  of  this  tube  is  too 
small  for  a  Pinnixa  to  pass,  it  must  enter  while  small  and  pass 
the  rest  of  its  life  there. 

The  period  of  moulting  is  dangerous,  not  only  because  of 
enemies,  but  also  because  of  its  critical  nature,  for  many  crabs 
die  in  the  act,  while  others  lose  their  limbs  and  their  gills.  The 
general  constitutional  disturbance  is  so  great  that  it  is  difficult  to 
carry  a  full-grown  crab  safely  through  it  in  an  aquarium.  The 
power  to  replace  lost  parts  which  is  so  well  developed  in  crabs 
is  an  adjustment  to  meet  and  compensate  for  this  danger  among 
others.  Most  of  the  direct  danger  comes  from  the  stony  hard- 
ness and  inflexibility  of  the  old  shell,  and  the  shells  of  crabs 
like  the  Pinnixa,  and  the  female  Pinnotheres  which  lives  within 
the  shell  of  the  oyster,  are  softer  than  those  of  more  exposed 
crabs. 

The  hermit-crabs  and  soldier-crabs  live  in  the  spiral  shells  of 
gasteropod  mollusks,  and,  as  these  houses  are  strong  enough  to 
furnish  ample  protection,  all  the  hinder  part  of  the  body  of  these 
crabs  is  covered  by  a  thin  flexible  shell  which  may  be  stripped 
off  without  danger,  although  the  claws  and  other  exposed  parts 
are  covered  by  very  hard  strong  shell.  When  born,  the  little  her- 
mit-crab is  straight  and  its  hind-body  carries  swimming  feet,  but 
when  it  is  about  as  large  as  a  mosquito,  these  become  converted 
into  knobs  for  clinging  to  the  inside  of  the  house,  and  the  hinc- 
body  becomes  twisted  into  a  spiral  to  fit  the  inside  of  the  spiral 
shell.  Crabs  outgrow  the  shells  of  mollusks  just  as  children  out- 
grow their  clothes ;  and  hermit-crabs  are  always  on  the  watch  for 
new  shells,  and  exhibit  what  the  human  observer  finds  himself 
disposed  to  call  a  lively  interest  in  shells.  If  half  a  dozen  of 
them  are  placed  in  an  aquarium,  they  soon  begin  to  measure  and 
compare  shells,  and  even  to  make  vacant  one  that  seems  eligible, 
by  pulling  out  its  occupant  piece  by  piece  and  eating  him.     One 


6  THE  FOUNDATIONS  OF  ZOOLOGY 

that  has  found  or  emptied  a  shell  that  seems  to  suit,  measures  it 
carefully  inside  and  out,  and  then,  bringing  the  openings  close 
together,  quickly  pops  out  of  the  old  into  the  new.  Then  the  old 
shell  is  compared  with  the  new,  and  often  the  body  is  slipped 
into  each  of  them  repeatedly,  and  each  is  allowed  to  slip  nearly 
off  and  is  then  pulled  on  again,  somewhat  as  a  man  settles  him- 
self into  a  new  coat.  Running  is  now  tried  in  each  shell,  a  claw 
keeping  a  tight  clutch  on  the  empty  one  and  dragging  it  along ; 
and  the  movement  of  drawing  the  body  far  into  the  shell,  so  that 
it  drops  on  the  sand  as  if  it  were  empty,  is  tried  in  both.  It  is 
often  many  hours  before  a  choice  is  made,  and  then  the  decision 
often  is  that  the  old  one  is  best. 

It  is  difficult  to  witness  or  to  describe  this  performance  with- 
out attributing  to  the  crab  feelings  and  motives  like  our  own ; 
yet,  while  no  one  can  say  whether  the  crab  knows  what  it  is 
about  or  not,  nothing  is  more  certain  than  that  its  actions  are 
due  to  its  nature,  and  not  to  knowledge  of  the  value  of  a  house, 
drawn  from  experience.  When  I  was  working  as  a  student  in  the 
marine  laboratory  of  Alexander  Agassiz,  he  reared  from  eggs,  in 
an  aquarium,  a  brood  of  hermit-crabs  which  had  never  seen  a 
shell.  I  had  in  my  aquarium  young  gasteropods  which  I  had 
reared  from  eggs.  Some  of  them  had  died,  and  their  empty 
shells  were,  at  his  suggestion,  dropped  into  the  water  with  the 
crabs,  which  seized  them,  almost  as  soon  as  they  touched  the 
water,  and  beginning  to  explore  their  interior  as  they  were  carried 
to  the  bottom  by  the  weight  of  the  shells,  conducted  themselves 
as  if  they  had  many  years  of  experience  in  the  use  of  molluscan 
shells  as  houses.  I  have  seen  very  young  hermit-crabs  make 
houses  for  themselves  out  of  the  cast  skins  of  others,  although 
these  afforded  no  protection ;  and  I  have  found  a  full-grown  one 
in  the  bowl  of  a  clay  pipe  so  badly  broken  that  it  exposed  the 
soft  abdomen  and  was  useless ;  but  the  impulse  to  inhabit  shells 
is  almost  universally  protective  and  beneficial,  although  it  is  as 
strictly  a  part  of  the  nature  of  hermit-crabs  as  is  the  twisted 
abdomen,  or  the  legs  and  claws,  or  any  other  part  of  the  crab's 
body. 

The  external  world  presents  such  variety  that  few  natural  ad- 
justments are  so  exact  and  definite  that  they  may  not  under  some 


INTRODUCTORY  7 

circumstances  prove  disadvantageous  or  even  destructive  instead 
of  beneficial,  although  the  perfection  of  many  of  the  adjustments 
of  Crustacea  and  insects  is  marvellous.  Some  hunting  wasps 
store  living  spiders  in  the  cells  with  their  eggs  to  serve  as  food 
for  their  young,  but  each  spider,  while  alive,  is  paralyzed  and 
helpless,  for  when  the  wasp  captures  it  she  stings  it  through  the 
nerve-centre  which  directs  the  movements  of  the  limbs,  severely 
enough  to  produce  paralysis  without  destroying  life ;  and  Mivart 
says  ("  Lessons  from  Nature,"  p.  202)  that  the  female  wasp  does 
this  by  nature  or  without  experience. 

It  is  often  said  that  the  natural  activities  of  living  things  are 
innate ;  but,  so  far  as  this  word  implies  that  they  take  place  with- 
out a  stimulus,  it  is  obviously  erroneous.  The  hermit-crab  is  said 
to  seek  a  house  by  nature,  and  the  Q.^g  to  grow  into  a  specific 
organism  in  virtue  of  its  inherent  potency ;  but  this  is  not  strictly 
"true,  for  while  some  vital  changes  may  be  spontaneous,  in  one  of 
the  many  meanings  of  this  word,  there  is  no  reason  to  believe 
that  any  change  ever  takes  place,  either  in  living  things  or  any 
where  else,  without  antecedents  which  stand  in  that  peculiar  rela- 
tion which  we  call  physical  causation. 

The  new-born  child  is  said  to  seek  the  breast  instinctively,  but 
every  nurse  knows  that  it  does  not  seek  the  breast  at  all  without 
experience,  although  it  does  suck  by  nature  and  without  instruc- 
tion the  first  time  the  nerves  of  its  lips  and  tongue  are  stimulated 
by  contact  with  the  nipple.  The  instinct  of  the  young  hermit-crab 
cannot  be  called  spontaneous,  if,  by  this  word,  we  mean  arbitrary, 
although  it  is  so  promptly  called  forth  by  the  first  sight  of  a  shell. 

The  bodily  movements  of  which  the  purpose  is  most  obvious 
are,  as  a  rule,  called  out  in  response  to  changes  in  the  external 
world,  and  they  are  excited  by  stimuli  which  come  through  the 
senses ;  although  many  responsive  actions  are  called  forth  by 
stimuli  which  arise  within  the  body  and  do  not  reach  it  through 
any  of  the  organs  of  special  sense,  as  the  stretching  of  our  limbs 
while  awakening  is  excited  by  the  vague  discomfort  of  the  body ; 
and  this  is  true  not  only  of  many  bodily  movements  but  of  most 
physiological  changes. 

"To  call  mind  a  function  of  the  brain,"  says  Maudsley  ("Re- 
sponsibility in  Mental  Disease,"  p.    17),    "may  lead    to   much   mis- 


8  THE  FOUNDATIONS   OF    ZOOLOGY 

apprehension  if  it  be  thereby  supposed  that  the  brain  is  the  only 
organ  which  is  concerned  in  the  function  of  mind.  There  is  not 
an  organ  in  the  body  which  is  not  in  intimate  relation  with  the 
brain  by  means  of  its  paths  of  nervous  communication,  .  .  .  and 
which  does  not,  therefore,  affect  more  or  less  plainly  and  specifi- 
cally its  function  as  an  organ  of  mind.  It  is  not  merely  that  a 
palpitating  heart  may  cause  anxiety  and  apprehension,  or  a  dis- 
ordered liver  gloomy  feelings,  but  there  are  good  reasons  for  be- 
lieving that  each  organ  has  a  specific  influence  on  the  constitution 
and  function  of  mind ;  an  influence  not  yet  set  forth  scientifically, 
because  it  is  exerted  on  that  unconscious  mental  life  which  is  the 
basis  of  all  that  we  consciously  feel  and  think.  Were  the  heart 
of  one  man,"  says  Maudsley,  "to  be  placed  in  the  body  of  another, 
it  would  probably  make  no  difference  in  the  circulation  of  the 
blood,  but  it  might  make  a  real  difference  in  the  temper  of  his 
mind.  So  close  is  the  physiological  sympathy  of  parts  in  the 
commonwealth  of  the  body,  that  it  is  necessary,  in  the  physiologi- 
cal study  of  mind,  to  regard  it  as  a  function  of  the  whole  organ- 
ism, as  comprehending  the  whole  bodily  life." 

A  most  notable  illustration  of  the  way  a  complicated  adaptive 
mechanism  may  be  thrown  into  beneficial  response  by  a  physio- 
logical stimulus,  is  found  in  the  shad,  which,  when  its  bodily 
structure  is  excited  by  the  reaction  of  approaching  sexual  matu- 
rity, leaves  its  home  in  the  ocean  and  enters  upon  a  journey 
which,  before  its  path  was  obstructed  by  dams,  carried  it  across 
the  broad  states  of  Virginia,  Maryland,  and  Pennsylvania,  to  its 
spawning  ground  in  central  New  York. 

The  excitement  of  adaptive  vital  changes  in  one  part  of  the  body 
by  changes  in  another  part  is  not  restricted  to  the  channels  afforded 
by  the  nervous  system.  Florists  make  their  plants  bloom  before 
their  time  by  confining  their  roots  in  small  pots.  The  seeds  of  an 
apple  are  new  beings,  but  the  apple  itself  is  part  of  the  substance  of 
the  mother-tree,  yet  the  blossoms  will  not  set  fruit  unless  they  are 
fertilized. 

When  a  duck's  o.^^  is  put  under  a  hen,  it  undergoes  a  long  series 
of  wonderful  changes,  which  all  prove,  in  the  end,  to  be  in  respon- 
sive adjustment  to  the  normal  life  of  ducks ;  and  as  the  production 
of  a  duck  by  the  mere  heat  of  a  hen,  or  that  of  a  lamp  in  an  incu- 


INTR  OD  UCTOR  Y  9 

bator,  is  incredible,  we  say  the  egg  is  developed  by  its  inherent 
potency ;  but  we  must  use  these  words  with  care,  for  the  assertion 
that  the  changes  which  make  up  this  long  and  marvellous  series 
take  place  spontaneously  is  as  incredible  as  the  assertion  that  they 
are  determined  by  the  heat  of  the  hen ;  and  there  is  reason  to  believe 
that  each  change  in  the  series  transmits  to  the  natural  or  inherent 
adaptive  mechanism  a  stimulus  which  excites  in  it  the  performance 
of  the  responsive  actions  which  bring  about  the  next  change  in 
order. 

Embryonic  development  is  so  delicate  and  so  complicated  that 
we  cannot  hope  to  trace,  far  less  to  imitate,  the  action  of  these 
stimuli  in  anything  like  their  natural  perfection  ;  yet  we  can,  now 
and  then,  rudely  imitate  some  of  them,  while,  in  other  cases,  we  can 
demonstrate  their  presence  and  influence  indirectly  by  preventing 
them  from  acting.  Some  eggs  which  have  begun  their  development 
by  division  into  two,  four,  or  eight  cells,  may  be  shaken  apart  with- 
out destroying  their  vitality,  and  when  thus  separated,  a  cell  which 
would  normally  have  given  rise  to  half  or  quarter  of  an  embryo,  may 
give  rise  to  a  whole  one  of  one  half  or  one  quarter  the  natural  size. 
Embryologists  are  rapidly  adding,  by  experimental  methods,  to  our 
knowledge  of  the  mechanics  of  development,  and  it  has  been  known, 
since  the  day  of  Aristotle,  that  some  of  the  latest  stages  in  the 
development  of  the  higher  animals  and  of  man  do  not  take  place  in 
the  absence  of  certain  normal  physiological  stimuli. 

Male  mammals,  for  example,  do  not  attain  bodily  perfection  until 
the  approach  of  sexual  maturity.  In  man  the  beard  begins  to  grow 
at  what  is  accordingly  called  the  age  of  pubescence ;  the  larynx 
enlarges ;  the  voice  assumes  a  manly  tone ;  the  shoulders  grow 
broad ;  the  chest  deepens ;  and  the  trunk  and  limbs  begin  to  differ 
in  relative  length  from  those  of  women  and  children.  At  the  same 
period  in  the  life  of  a  bull  his  neck  and  shoulders  grow  massive  and 
sturdy ;  his  forehead  broadens  and  becomes  cushioned  with  hair ;  and 
he  becomes  pugnacious  and  subject  to  fits  of  violent  rage. 

The  cock  acquires  his  spurs,  his  brilliant  plumage  and  other 
ornaments,  and  begins  to  crow.  Aristotle  pointed  out  that  when 
young  male  mammals  or  birds  are  prevented  from  becoming  sexually 
mature,  they  fail  to  acquire  the  distinctive  characteristics  of  their 
species,  and  this  shows  that  the  completion  of  this,  the  final   stage 


10  THE  FOUNDATIONS   OF  ZOOLOGY 

in  their  physical  development,  is  dependent,  to  a  great  degree  at 
least,  on  some  constitutional  stimulus  which  is  afforded  by  the 
changes  which  take  place  in  the  reproductive  organs. 

The  existence  of  rudimentary  organs  and  provisional  larval 
stages  is  one  of  the  most  suggestive  facts  in  the  whole  range  of 
zoology,  and  the  evidence  that  these  things  are  a  record  of  past 
history  seems  conclusive ;  although  those  who  hold  that  their 
existence  is  accounted  for  by  the  discovery  that  they  are  a 
"recapitulation"  add  nothing,  after  all  the  centuries,  to  Aristotle's 
declaration  that  they  are  "for  a  token." 

They  who  are  most  convinced  that  the  historical  significance 
of  these  structures  is  an  adequate  explanation  of  their  presence, 
are  also  most  emphatic  in  their  repudiation  of  teleology,  and  in  the 
rejection  of  the  belief  of  Louis  Agassiz,  that  they  are  part  of  the 
language  in  which  the  Creator  tells  us  the  history  of  creation ; 
yet  the  assertion  that  their  history  accounts  for  their  existence  is 
as  teleological  as  anything  in  Paley. 

They  who  believe  that  inheritance  is  not  the  transmission  of  re- 
sponsive actions,  but  the  transmission  of  an  adaptive  mechanism,  and 
that  each  change  which  enters  into  the  history  of  development  is  a 
response  to  a  stimulus,  will  have  no  difficulty  in  understanding  that 
organs  which  were  once  adjusted  to  the  external  world  may,  after 
this  adjustment  has  lost  its  meaning,  be  still  retained,  because  they 
furnish  physiological  stimuli,  which  excite  developmental  changes 
in  the  organic  mechanism. 

If  a  physiological  stimulus  from  the  male  reproductive  organs 
excites  the  growth  of  weapons  of  defence,  would  the  preservation 
of  rudiments  of  these  organs,  by  natural  selection,  for  this  useful 
purpose,  be  anything  more  than  might  be  expected ;  even  if  some 
change  in  the  method  of  reproduction  should  make  their  primary 
function  useless.'' 

Is  there  any  evidence  that  any  change  which  is  due  to  nature, 
from  the  segmentation  of  the  o.^^  to  old  age,  ever  takes  place 
without  a  stimulus,  or  are  the  actions  which  are  due  to  nature 
beneficial,  except  so  far  as  the  environment  is,  on  the  average, 
like  the  ancestral  environment .-'  Since  the  gentle  stimulation  of 
the  lips  and  tongue  has  been  associated,  in  the  past  history  of 
human  infants,  with  the  presence  of  milk  which  may  be  extracted 


INTRODUCTORY  II 

by  sucking,  the  adjustment  is  beneficial;  although  the  infant  does 
not,  as  a  matter  of  fact,  obtain  any  milk  at  first,  and  although  a 
finger  or  a  rubber  nipple  on  an  empty  bottle,  or  any  other  object 
of  suitable  size  and  texture,  in  the  mouth  of  a  hungry  infant, 
excites  the  nerves  and  muscles  so  as  to  call  forth  the  act  of  suck- 
ing, and,  so  far,  to  satisfy  the  calls  of  nature. 

Preyer  says  "  when  I  put  into  the  mouth  of  the  screaming 
child,  whose  head  alone  was  as  yet  born,  the  ivory  pencil  or  a 
finger,  the  child  began  to  suck,  opened  its  eyes,  and  seemed,  to 
judge  from  its  countenance,  to  be  most  agreeably  affected.  In 
the  case  of  another  child,  which  cried  out  immediately  after  its 
head  emerged  from  the  womb,  I  put  my  finger,  three  minutes 
later,  into  the  child's  mouth,  and  pressed  it  on  the  tongue.  At 
once  all  crying  ceased,  a  brisk  sucking  began,  and  the  expression 
of  the  countenance,  which  had  been  hitherto  discontented,  became 
suddenly  altered.  The  child,  not  yet  fully  born,  seemed  to  expe- 
rience something  agreeable,  and  therewith  —  during  the  sucking 
of  the  finger  —  the  eyes  were  widely  opened." 

Although  changes  which  are  directly  due  to  nature  do  not 
take  place  without  a  stimulus,  they  do  take  place  mechanically, 
or  independently  of  experience,  under  the  natural  stimulus,  or 
under  any  other  which  is  applied  in  the  same  way.  The  blow- 
fly, which  is  stimulated  by  the  odor  of  putrid  flesh  to  lay  its  eggs 
where  the  larvae  will  find  abundant  food,  sometimes  lays  them  on 
the  stinking  arum,  misled  by  its  odor.  In  this  case  the  deceptive 
stimulus  resembles  the  normal  one  in  certain  sensible  qualities, 
but  it  is  most  important,  for  reasons  which  will  be  given  later, 
to  note  that  the  natural  responses  of  living  things  may  be  called 
forth  by  any  stimulus  which  is  similar  /;/  its  mode  of  application 
to  the  normal  or  natural  stimulus,  whether  it  is  or  is  not  similar 
in  any  sensible  properties  except  those  which  act  as  the  stimulus. 
The  finger,  which  feels  like  a  nipple,  stimulates  the  infant  and 
calls  out  the  sucking  response,  but  electrical  stimulation  of  the 
lips  and  tongue,  if  applied  with  sufficient  skill,  might  give  the 
same  result,  although  this  does  not  resemble  the  nipple  in  any 
sensible  qualities  except  the  ones  which  effect  the  stimulation. 

In  the  order  of  nature  each  stimulus  is  a  sign  with  a  signifi- 
cance,   and    our    own    reason,    which    consciously    apprehends    the 


12  THE  FOUNDATIONS  OF  ZOOLOGY 

significance  of  natural  signs,  generally  approves  the  responsive 
actions  of  living  things,  although  we  find  that  these  living  things 
are  often  misled  by  signs  which  we  know  to  be  illusions,  which, 
while  similar  in  some  respects  to  those  to  which  the  organic 
mechanism  is  adjusted,  signify  something  quite  different  from  the 
normal  or  customary  course  of  events. 

As  the  nature  of  living  things  often  leads  to  injurious  or  de- 
structive actions,  instinct  is  said  to  be  blind  or  mechanical ;  for  while 
no  one  can  say  whether  the  actions  of  the  hermit-crab  or  those 
of  the  blow-fly,  or  those  of  the  human  infant,  are  voluntary  or  not, 
they  are  no  more  than  the  nature  of  these  living  things  would 
lead  one  to  expect,  and  this  is  as  true  when  they  are  beneficial 
as  it  is  when  they  mislead. 

If  the  adjustments  between  living  things  and  the  external 
world  were  always  beneficial,  I  do  not  see  how  the  question 
whether  or  not  their  actions  are  voluntary  could  present  itself ; 
but  the  complexity  of  external  nature  is  inexhaustible,  and  few 
natural  adjustments  are  beneficial  under  all  circumstances,  for  even 
a  response  to  gravitation  may  mislead. 

A  growing  plant  needs  the  moisture  and  the  soluble  food 
which  it  may  find  under  ground,  in  course  of  nature,  by  follow- 
ing the  stimulus  of  gravity,  and  it  also  needs  the  sunlight  and 
the  air  which,  in  the  normal  or  natural  order  of  things,  are  to  be 
reached  by  upward  growth.  As  the  seed  germinates,  the  radicle, 
stimulated  by  gravity,  grows  downwards,  while  the  plumule,  which 
does  not  differ  essentially  from  the  radicle  in  specific  gravity,  is 
impelled  by  its  nature  to  grow  upwards  under  the  same  stimulus; 
but  each  part  grows  by  means  of  internal  energy,  and,  while 
gravity  is  the  stimulus  which  throws  it  into  action,  it  is  not  the 
means  by  which  the  vital  changes  are  brought  about. 

The  response  is  beneficial,  and  the  stimulus  seems  as  trust- 
worthy as  anything  in  nature ;  yet  the  seeds  often  fall  into  places 
where  it  misleads.  If  a  germinating  seed  be  placed  on  the 
edge  of  a  horizontal  wheel  which  turns  slowly  at  a  rate  which 
makes  the  centrifugal  force  somewhat  greater  than  the  weight  of 
the  seed,  the  plumule  grows  towards  and  the  radicle  away  from 
the  centre,  although  no  seeds  which  act  thus  can  grow  up  to 
produce  seeds  in  their  turn.     If   plants  think,  a   matter   on  which 


INTR  OD  UCTOR  Y  1 3 

I  do  not  here  express  an  opinion,  they  must  know  the  order 
of  nature  to  which  they  respond,  and  in  that  case  the  seed  on 
the  wheel  would  seem  to  be  not  only  misled  but  deceived,  exactly 
as  a  brood  of  chicks  seems  to  us  to  be  deceived  by  an  imitation 
of  the  call  of  the  mother  hen ;  but  the  essential  point  is  that, 
whether  they  know  it  or  not,  the  changes  in  living  things  which 
are  directly  due  to  nature  are  beneficial  only  so  far  as  the  condi- 
tions of  their  life  are,  on  the  average,  essentially  like  those  in 
which  the  lives  of  their  ancestors  were  passed. 

Now  the  order  of  nature  presents  infinite  diversity :  the  differ- 
ent ways  in  which  events  may  be  combined  are  innumerable ;  and 
no  natural  response  can  be  judicious  or  beneficial  under  all  cir- 
cumstances. We  accordingly  find,  in  all  the  living  things  we 
know  best,  and  are  most  intimately  concerned  with,  a  wonderful 
provision  of  their  nature,  by  means  of  which  those  of  their  actions 
which  are  most  apt  to  mislead  are  improved  and  perfected  and 
developed  by  normal  use,  so  that  we  are  no  longer  able  to  tell 
what  they  will  do  from  knowledge  of  their  nature  alone,  since 
their  actions  are  in  part  dependent  on  their  training  and  expe- 
rience, and  on  their  individual  contact  with  the  world. 

The  question  whether  capacity  for  improvement  through  con- 
tact with  the  world  is  natural  or  not  is  much  easier  to  ask  than 
to  answer.  Are  the  benefits  that  attend  training  and  education 
and  experience  part  of  the  nature  of  living  things,  or  do  they  add 
to  nature  something  it  did  not  before  contain  .''  Is  knowledge  of 
the  world  around  us  part  of  our  nature,  or  does  it  add  something 
new  on  to  our  nature .''  If  it  is  natural,  do  we  simply  find  or  dis- 
cover our  nature,  or  do  we  make  it  or  any  part  of  it  ourselves  ? 
Any  answer  we  try  to  give  is  attended  with  difficulties.  If  living 
things  make  any  part  of  their  nature,  the  word  must  mean  much 
more  than  is  recognized  in  common  usage ;  and  yet  the  assertion 
that  knowledge  and  experience  and  training  add  nothing  to  the 
nature  of  living  beings  is  beset  by  difficulties  which  at  first  sight 
seem  equally  grave. 

In  some  cases  we  can  show  that  improvement  by  training  is 
no  more  than  might  have  been  expected,  for  we  can  imitate  it 
by  means  of  stimuli  which  have  nothing  in  common  with  the 
natural   stimuli   except   the    manner   of   their   application.     Normal 


i4  THE  FOUNDATIONS   OF  ZOOLOGY 

use  strengthens  muscles  and  increases  their  aptitude  for  doing 
their  work,  but  as  muscles  may  also  be  strengthened  by  massage, 
their  improvement  by  use  is  no  more  than  their  nature  might 
have  led  us  to  look  for;  nor  do  we  find  any  more  difificulty  in 
attributing  this  beneficial  response  to  nature  than  we  find  in  the 
same  explanation  of  the  house-hunting  actions  of  crabs. 

All  who  have  to  do  with  animals  admit  that  training  can  do 
no  more  for  them  than  to  make  the  best  of  their  natural  capa- 
city, for  they  differ  greatly  in  power  to  profit  by  experience ;  and 
the  nature  of  each  species  sets  impassable  bounds  to  the  power 
of  individual  animals  to  improve  by  practice.  No  one  hesitates 
to  attribute  to  deficient  structure  the  inability  of  idiots  to  learn, 
and  all  admit  that  men  of  genius  are  born  and  not  made,  yet 
many  hesitate  to  confess  that  their  own  more  commonplace 
capacity  for  profiting  by  practice  and  growing  wiser  with  experi- 
ence is  strictly  limited  by  their  nature,  although  this  may  be 
quite  obvious  to  others.  All  know  too  well  also  that  a  dose  of 
alcohol  may  make  a  man  remember  what  never  happened  outside 
his  own  disordered  brain,  and  perform  responsive  actions  which,  while 
criminal,  might  be  prudent  and  commendable  if  the  remembered 
experience  were  not  a  delusion ;  although  the  effects  of  contact  with 
the  world  are  usually  far  too  complicated  and  diversified  to  be  artifi- 
cially imitated.  As  we  are  quite  unable  to  tell  with  any  minute 
accuracy  what  an  animal  with  capacity  for  training  will  do  under 
a  stimulus,  we  must  rely  upon  indirect  evidence  to  show  what  the 
real  significance  of  experience  is. 

If  a  chick  is  stung  by  the  first  honey-bee  it  catches,  its  future 
actions  may  be  adjusted  to  the  natural  law  that  bees  are  danger- 
ous; but  if,  before  it  is  stung,  it  has  captured  and  eaten  stingless 
drones,  it  may  act  in  accordance  with  the  wider  law  that  while 
bees  are  good  for  food  some  are  dangerous.  A  careful  observer, 
Mr.  Oilman  Drew,  tells  me  that  the  chicks  that  are  most  destruc- 
tive to  bees  pick  out  the  drones,  and  he  believes  that  these  are 
the  chicks  which,  before  they  were  stung,  learned  to  catch  and 
€at  bees,  and  that  they  have  afterwards  learned  to  let  the  sting- 
ing workers  alone. 

If  slight  differences  in  the  mere  order  of  events  which  are 
otherwise  so  much  alike  may  lead  to  such  differences  in  the   con- 


INTRODUCTORY  1 5 

duct  of  individual  animals  of  the  same  species,  it  is  clear  that 
even  if  we  believe  that  sufficient  knowledge  of  their  nature  would 
enable  us  to  predict  their  conduct,  this  knowledge  is  unattainable, 
for  we  cannot  possibly  know  all  the  complicated  personal  history 
of  any  one  animal.  We  must  also  remember  that  even  if  we 
prove  that  individual  animals  acquire,  by  contact  with  the  ex- 
ternal world,  nothing  but  what  their  nature  provides  for,  this 
does  not  show  that  they  are  compelled  to  make  of  themselves  all 
that  their  nature  permits,  for  the  effects  of  experience  are  often 
injurious  or  destructive.  There  is,  unfortunately,  no  incompati- 
bility between  the  system  of  things  and  unprofitable  experience, 
for  it  is,  to  say  the  least,  no  harder  to  corrupt  or  injure  nature  by 
injudicious  or  pernicious  training  than  it  is  to  make  the  best  of  it. 

Romanes  tells  us  ("  Mental  Evolution  in  Animals,"  p.  215)  of  a 
hen  that  had  reared  three  successive  broods  of  ducklings  in  suc- 
cessive years,  and  then  hatched  out  a  brood  of  nine  chickens : 
"  The  first  day  she  was  let  out  she  disappeared,  and  after  a  long 
search  my  sister,"  his  informant  writes,  "found  her  beside  a  little 
stream,  which  her  successive  broods  of  ducklings  had  been  in  the 
habit  of  frequenting.  She  had  got  four  of  her  chickens  into  the 
water,  which,  fortunately,  was  very  shallow  at  the  time.  The  other 
five  were  all  standing  on  its  margin,  and  she  was  endeavoring  by 
all  sorts  of  coaxing  hen-language,  and  by  pushing  each  chicken 
in  turn  with  her  bill,  to  get  them  into  the  water  also." 

In  the  normal  course  of  the  history  of  chicks,  the  response  to 
the  order  of  nature  which  experience  is  said  to  have  called  out 
in  this  hen,  would  be  rapidly  fatal  to  her  posterity ;  and  it  would 
be  easy  to  give  other  illustrations  to  show  that  the  changes  which 
are  called  forth  in  living  things  by  the  influence  of  the  world 
around  them,  are  beneficial  only  so  far  as  this  external  world  is, 
on  the  average,  substantially  the  same  as  that  to  which  the  actions 
of  their  ancestors  were  adjusted.  The  snake  that  swallows  hens' 
eggs,  like  its  ancestors,  profits  like  them ;  but  the  snake  that 
swallows  a  china  nest-egg  dies  from  indigestion.  I  shall  try  to 
show  that  this  fact,  and  others  like  it,  mean  that  while  the  changes 
would  not  take  place  without  practice  or  training,  their  character 
is  due  to  nature,  and  not  to  experience. 

It  is  almost    impossible  to   contemplate  the  actions  of   animals 


l6  THE  FOUNDATIONS  OF  ZOOLOGY 

that  profit  by  experience,  without  attributing  them  to  conscious 
intelligence,  and  it  is  even  harder  to  speak  or  write  of  them,  with- 
out using  words  which  imply  that  they  are  altogether  such  as 
human  actions  would  be  under  like  conditions,  for  our  words  are 
adapted  to  human  needs ;  but,  hard  as  it  is,  we  must,  so  far  as 
possible,  distinguish  what  we  actually  observe  from  what  we  infer 
from  our  knowledge  of  ourselves. 

He  who  considers  the  relation  between  mind  and  matter  should 
try  to  determine  clearly  what  he  knows  and  does  not  know  about 
the  distribution  of  mind.  Is  not  the  view  of  the  matter  to  which  all 
should  agree,  about  as  follows .-'  I  know  my  mental  state  and  the 
things  I  see  and  feel  by  the  best  of  all  evidence.  While  I  have  not 
this  sort  of  evidence  for  anything  else,  doubt  that  my  fellow-men 
are  rational  would  be  regarded  as  insane ;  for  he  who  acts  as  if  his 
fellow-men  have  no  feelings,  is  justly  abhorred  by  all,  unless,  indeed, 
he  is  held  in  honor  as  a  military  hero.  "  A  close  study  of  the  dog," 
says  Agassiz,  "  might  satisfy  every  one  of  the  similarity  of  his 
impulses  with  those  of  man,  and  those  impulses  are  regulated  in  a 
manner  which  discloses  psychical  faculties  in  every  respect  of  the 
same  kind  as  those  of  man ;  moreover,  he  expresses  by  his  voice 
his  emotions  and  his  feelings,  with  a  precision  which  may  be  as 
intelligible  to  man  as  the  articulate  speech  of  his  fellow-men.  His 
memory  is  so  retentive  that  it  frequently  baffles  that  of  man.  And 
though  all  these  faculties  do  not  make  a  philosopher  of  him,  they 
certainly  place  him,  in  that  respect,  upon  a  level  with  a  consider- 
able proportion  of  poor  humanity." 

"  When  animals  fight  with  one  another,  when  they  associate  for 
a  common  purpose,  when  they  warn  one  another  in  danger,  when 
they  come  to  the  rescue  of  one  another,  when  they  display  pain 
or  joy,  they  manifest  impulses  of  the  same  kind  as  those  which  are 
considered  among  the  moral  attributes  of  man.  The  range  of  their 
passions  is  even  as  extensive  as  that  of  the  human  mind,  and 
I  am  at  a  loss  to  distinguish  a  difference  in  kind  between  them, 
however  much  they  may  differ  in  degree  and  in  the  manner  in 
which  they  are  expressed." 

"  I  confess,"  says  Agassiz,  "  I  could  not  say  in  what  the 
mental  faculties  of  a  child  differ  from  those  of  a  young  chim- 
panzee." 


INTRODUCTORY  ij 

While  the  evidence  does  not  have  that  highest  degree  of  value 
which  I  find  in  my  own  feelings,  good  common  sense  seems  to 
demand  that  the  burden  of  proof  fall  on  those  who  hold  that 
apes  and  dogs  and  elephants  are  not  rational. 

"Who,"  asks  Agassiz,  "is  the  investigator,  who  having  once 
recognized  such  a  similarity  between  certain  faculties  of  man  and 
those  of  the  higher  animals,  can  feel  prepared,  in  the  present 
stage  of  our  knowledge,  to  trace  the  limit  where  this  community 
of  nature  ceases  ?  " 

As  for  myself,  I  try  to  treat  all  living  things,  plants  as  well 
as  animals,  as  if  they  may  have  some  small  part  of  a  sensitive 
life  like  my  own,  although  I  know  nothing  about  the  presence  or 
absence  of  sense  in  most  living  things ;  and  am  no  more  prepared 
to  make  a  negative  than  a  positive  statement.  While  it  is  non- 
sense to  regard  trees  and  rocks  and  lakes  as  endowed  with  mind, 
it  is  nonsense  because  we  know  nothing  about  it,  and  not  because 
it  is  untrue  ;  for  it  is  no  less  nonsense  to  assert  that  stones  are 
unconscious  than  to  assert  that  they  are  conscious. 

Morgan  says  ("Habit  and  Intelligence,"  p.  41),  "To  some 
chicks  I  threw  cinnabar  larvae,  distasteful  caterpillars  conspicuous 
by  alternating  rings  of  black  and  golden  yellow.  They  were  seized 
at  once,  but  dropped  uninjured;  the  chicks  wiped  their  bills  —  a 
sign  of  distaste  —  and  seldom  touched  the  caterpillars  a  second 
time.  The  cinnabar  laryas  were  then  removed,  and  thrown  in 
again  towards  the  close  of  the  day.  Some  of  the  chicks  tried 
them  once,  but  they  were  soon  left.  The  next  day  the  young 
birds  were  given  brown  loopers  and  green  cabbage-moth  cater- 
pillars. These  were  approached  with  some  suspicion,  but  pres- 
ently one  chick  ran  off  with  a  looper,  and  was  followed  by  others, 
one  of  which  stole  and  ate  it.  In  a  few  minutes  all  the  cater- 
pillars were  cleared  off.  Later  in  the  day  they  were  given  some 
more  of  these  edible  caterpillars,  which  they  ate  freely ;  and  then 
some  cinnabar  larvae.  One  chick  ran,  but  checked  himself,  and, 
without  touching  the  caterpillar,  wiped  his  bill  —  a  memory  of  the 
nasty  taste  being  apparently  suggested  at  the  sight  of  the  yellow 
and  black  caterpillar;  another  seized  one  and  dropped  it  at  once. 
A  third  subsequently  approached  a  cinnabar  as  it  crawled  along, 
gave  the  danger  note,  and  ran  off.  Then  I  threw  in  more  edible 
c 


l8  THE  FOUNDATIONS   OF  ZOOLOGY 

caterpillars,  which  again  were  eaten  freely.  The  chicks  had  thus 
learnt  to  distinguish  by  sight  between  the  nice  and  nasty  cater- 
pillars." 

"  The  cinnabar  caterpillars  are,  as  I  have  said,  conspicuously 
marked  with  alternating  yellow  and  black  rings.  It  would  seem 
that  the  end  of  this  conspicuousness  is  to  render  association  in 
the  individual  experience  of  young  birds  more  rapid  and  more 
certain  ;  there  does  not  appear  to  be  any  congenital  and  instinc- 
tive avoidance  of  such  caterpillars  with  warning  colors.  The  net 
result  of  these  observations  is  that,  in  the  absence  of  parental 
guidance,  the  young  birds  have  to  learn  for  themselves  what  is 
good  to  eat,  and  what  is  distasteful,  and  have  no  instinctive 
aversions." 

In  his  discussion  of  these  most  instructive  observations,  the 
author  says,  p.  150:  "A  chick  sees  for  the  first  time  in  its  life 
a  cinnabar  larva,  instinctively  pecks  at  it  under  the  influence  of 
the  visual  stimulus ;  seizes  it,  and  under  the  influence  of  the  taste- 
stimulus  instinctively  shrinks.  So  far  we  have  instinct  and 
automatism.  Presently  we  throw  to  it  another  similar  caterpillar. 
Instinct  and  automatism  alone  would  lead  to  a  repetition  of  the 
previous  series  of  events  ;  seeing,  seizing,  tasting,  and  shrinking. 
The  oftener  the  experiment  was  performed,  the  more  smoothly 
would  the  organic  mechanism  work,  the  more  definitely  would  the 
same  sequence  be  repeated  —  seeing,  seizing,  tasting,  shrinking. 
Is  this  what  we  actually  observe .''  '  Not  at  all.  On  the  second 
occasion  the  chick,  under  the  influence  of  the  previous  experience, 
acts  differently.  Though  he  sees,  he  does  not  seize,  but  shrinks 
without  seizing.  We  believe  that  there  is  a  revival  in  memory  of 
the  nasty  taste.  And  in  this  we  seem  justified,  since  we  may 
observe  that  sometimes  the  chick  on  such  occasions  wipes  the 
bill  on  the  ground  as  he  does  on  experiencing  an  unpleasant 
taste,  though  he  has  not  touched  the  larvas.  The  chick,  then, 
does  not  continue  to  act  merely  from  instinct  and  like  an  automa- 
ton. His  behavior  is  modified  in  the  light  of  previous  experi- 
ence." 

So  far  as  our  senses  tell  us,  actions  of  this  sort  are,  in  all 
respects,  like  many  we  observe  in  our  fellow-men,  and  attribute  to 
consciousness  and    memory  and   reason ;    and  as  a  mistaken  belief 


INTRODUCTORY  1 9 

that  the  brutes  are  conscious  can  do  no  harm,  while  belief  that 
they  are  unconscious  might,  if  mistaken,  bring  untold  misery  upon 
dumb  brutes  from  brutal  men,  it  seems  well  that  we  should  con- 
tinue to  describe  their  actions  in  subjective  language ;  although 
nothing  is  more  obvious  than  that,  while  we  know  their  actions, 
we  only  infer  the  existence  of  mental  accompaniments.  For  all 
any  one  knows  to  the  contrary  young  chicks  may  learn  what  is 
good  to  eat  and  what  is  unpleasant,  and  may  readily  associate  the 
appearance  with  the  taste,  and  those  who  hold  that  they  are  un- 
conscious may  justly  be  called  upon  by  Morgan  to  prove  their 
opinion ;  but  I  cannot  agree  with  him  that  his  studies  show  that 
they  are  conscious,  for  in  sober  and  scientific  truth  all  they  show 
is  that  the  chicks  rapidly  acquire  power  to  respond  to  certain 
optical  stimuli  by  actions  which  are  adjusted  to  those  flavors 
which  in  course  of  nature  are  associated  with  certain  optical 
properties. 

They  who  live  in  the  hope  that  the  actions  which  the  chick 
performs  only  after  what  we  call  experience,  will  sometime  be 
proved  as  mechanical  as  the  response  of  the  growing  seedling 
to  gravitation,  may  appeal  to  the  rapid  progress  which  physiol- 
ogists are  making  in  the  localization  of  the  functions  of  the 
brain,  as  evidence  that  their  hope  is  well  founded.  They  may 
say  that  there  is  good  reason  to  believe  that,  if  the  localized  and 
specialized  brain-cells  which  are  stimulated  through  the  eyes  and 
the  optic  nerves  by  the  yellow  and  black  rings  of  the  cinnabar 
caterpillar,  could  be  stimulated  by  electricity  or  in  any  other  way 
with  sufficient  delicacy  and  skill,  all  the  other  changes  which 
make  up  the  response  would  follow  mechanically ;  that  the  nervous 
discharge  from  these  cells  would  be  accompanied,  as  it  has  been 
before,  by  the  stimulation  of  those  localized  cells  which  were  origi- 
nally stimulated  by  the  pernicious  flavor,  and  that  the  nervous 
discharge  from  them  would  inhibit  the  seizing  movements,  and 
that  whether  the  chick  is  conscious  or  not,  the  establishment  of 
the  response  by  experience  is  no  more  than  might  have  been 
expected  from  our  knowledge  of  the  functions  of  the  nervous 
system. 

If  we  answer  that  this  is  as  yet  unproved,  inasmuch  as  no  one 
is   able    now,   or  is  at  all  likely  to   soon  be  able,  to  even  demon- 


20  THE  FOUNDATION'S   OF  ZOOLOGY 

strate,  far  less  to  imitate,  in  the  brain  of  the  chick,  any  struct- 
ural equivalent  to  its  experience,  we  may  be  told  that  no  one 
expects  complete  inductive  proof  of  any  scientific  generalization ; 
that  he  who  refuses  to  admit  that  all  water  consists  of  H2O  until 
chemists  have  decomposed  every  drop  of  water  in  the  ocean  is 
lacking  in  good  sense ;  and  that  it  is  equally  unreasonable  to  de- 
mand the  artificial  imitation  of  all  the  responses  of  living  things 
before  we  admit  that  all  response  is  mechanical. 

To  this  we  must  answer  that  no  great  harm  can  be  done  if 
the  chemist  interprets  the  admission  that  we  have  not  the  slight- 
est reason  to  doubt  that  every  drop  of  water  is  decomposable  into 
hydrogen  and  oxygen  as  an  assertion  that  all  water  is  so  decom- 
posable, since,  for  all  the  ordinary  purposes  of  chemistry,  the 
negative  admission  and  the  positive  assertion  may  be  treated  as 
if  they  were  synonymous.  The  case  is  very  different  when  the 
subject  under  consideration  is  not  chemistry,  but  the  nature  of 
knowledge,  for  we  are  about  to  enter  a  field  where  we  may  easily 
lose  our  way  unless  we  distinguish  inference  from  perception,  to 
the  best  of  our  ability.  The  utmost  the  physiologist  is  warranted 
in  asserting  is  that,  for  all  one  knows  to  the  contrary,  every 
response  may  be  mechanical ;  and  I  think  all  thoughtful  students 
must  so  far  agree  with  him  as  to  admit  that  belief  that  any  of  the 
responsive  actions  of  living  beings  are  not  mechanical  is  highly 
unwise  and  precarious,  in  view  of  the  condition  and  prospects  of 
modern  physiology ;  although  we  must,  in  my  opinion,  also  admit 
that  not  one  single  vital  response  has  as  yet  been  completely  ana- 
lyzed, or  resolved,  from  beginning  to  end,  into  phenomena  of  matter 
and  motion ;  for  I  am  myself  unable  to  discover,  in  the  present 
status  of  biology,  any  demonstration  of  error  in  the  assertion  that 
life  is  different  from  matter  and  motion. 

However  this  may  be,  we  know,  by  evidence  which  no  one  can 
question,  that  many  actions  are  attended  by  memory,  and  by  con- 
scious experience,  and  by  volition  and  reason  and  a  sense  of  moral 
responsibility.  Many  beneficial  responses  are  known  to  be  judicious 
and  reasonable,  and  many  voluntary  acts  are  known  to  be  right 
or  wrong. 

As  these  convictions  seem,  at  first  sight,  to  be  contradictory  to 
the  opinion  that,  for  all  we  know  to  the  contrary,  all  response  may 


INTRODUCTORY  21 

be  mechanical,  we  must  ask  whether  this  contradiction  is  real  or 
only  apparent.  As  this  question  has,  in  one  form  or  another,  vexed 
the  mind  of  man  for  untold  ages,  no  one  would  be  so  bold  as  to 
attempt  a  final  answer  in  few  words;  but  I  hope  all  who  follow 
me  to  the  end  may  find  reason  to  ask  themselves  whether  the  con- 
tradiction may  not,  after  all,  be  a  matter  of  words  rather  than  a  real 
difificulty,  for  I  shall  try  to  review,  at  one  time  and  another,  some 
of  the  evidence  which  has  convinced  many  thoughtful  men  that  this 
apparently  insoluble  puzzle  has  arisen  from  an  erroneous  and  un- 
scientific conception  of  the  meaning  of  the  mechanism  of  nature. 
This  evidence  seems  so  clear  and  conclusive  that  I  cannot  see  how 
any  one  who  has  mastered  it  can  find  any  contradiction  between 
anything  we  find  in  our  nature  and  the  ultimate  reduction  of  all 
nature,  including  all  the  phenomena  of  life  and  of  mind,  to  mechani- 
cal principles;  for  most  students  of  the  principles  of  science  agree 
that  natural  knowledge  is  no  more  than  the  discovery  of  the  order 
of  nature;  although  a  moment's  thought  is  enough  to  show  that  the 
fact  that  events  do  take  place  in  order  is  no  reason  why  they  should, 
or  even  why  they  should  take  place  at  all.  Order  is  no  explanation, 
but  a  thing  to  be  explained. 

The  proof  that  there  is  no  necessary  antagonism  between  me- 
chanical explanations  of  human  life  and  belief  in  volition  and  duty 
and  moral  responsibility  seems  to  me  to  be  very  simple  and  easy 
to  understand.  If  the  subject  takes  us  into  deep  waters,  this  is 
b)ecause  we  are  compelled  to  examine  the  reason  why  the  impres- 
sion that  these  things  are  antagonistic  has  so  widely  prevailed;  for 
the  view  of  the  matter  to  which  I  hope  to  call  your  attention  is,  in 
itself,  by  no  means  difficult  or  obscure. 

Science  is  still  in  its  infancy,  and  we  know  so  little  that  I  have 
no  sympathy  with  those  who  discount  the  .possibilities  of  future  dis- 
covery and  assert  that  life  is  merely  a  question  of  matter  and 
motion,  although  I  know  no  reason  why  this  should  not,  some  day, 
be  proved,  nor  am  I  able  to  see  why  any  should  find  this  admis- 
sion alarming. 

However  this  may  be,  I  am  convinced  that  they  stand  on 
treacherous  ground,  who  base  positive  opinions  on  negative  evi- 
dence, and  believe  that  anything  in  our  nature  is  inconsistent  with 
mechanics. 


22  THE  FOUNDATIONS   OF  ZOOLOGY 

"  Conscience,  the  last  acquired  faculty,"  says  Maudsley,  "  is  the 
first  to  suffer  when  disease  invades  the  mental  organization.  One 
of  the  first  symptoms  of  insanity  —  one  which  declares  itself  before 
there  is  any  intellectual  derangement,  before  the  person's  friends 
suspect  even  that  he  is  becoming  insane  —  is  a  deadening  or  com- 
plete perversion  of  the  moral  sense.  In  extreme  cases  it  is  observed 
that  the  modest  man  becomes  presumptuous  and  exacting,  the  chaste 
man  lewd  and  obscene,  the  honest  man  a  thief,  and  the  truthful  man 
an  unblushing  liar.  Short  of  this,  however,  there  is  an  observable 
impairment  of  the  finer  moral  feelings  —  a  something  different, 
which  the  nearest  friends  do  not  fail  to  feel,  although  they  cannot 
always  describe  it.  Now  these  signs  of  moral  perversion  are  really 
the  first  symptoms  of  a  mental  derangement  which  may,  in  its 
further  course,  go  through  all  the  degrees  of  intellectual  disorder, 
and  end  in  destruction  of  mind,  with  visible  destruction  of  the  nerve- 
cells  which  minister  to  mind.  Is  the  end,  then,  dependent  upon 
organization,  and  is  the  beginning  not .-' " 

"  Note,  again,  the  effect  which  a  severe  attack  of  insanity  some- 
times produces  upon  the  moral  nature  of  the  individual.  The  per- 
son entirely  recovers  his  reason ;  his  intellectual  faculties  are  as  acute 
as  ever,  but  his  moral  character  is  changed ;  he  is  no  longer  the 
moral  man  that  he  was ;  the  shock  has  destroyed  the  finest  part  of 
his  organization.  Henceforth  his  life  may  be  as  different  from  his 
former  life  as,  in  an  opposite  direction,  was  the  life  of  Saul  of  Tarsus 
from  the  life  of  Paul  the  Apostle  to  the  Gentiles.  An  attack  of 
epilepsy  has  produced  the  same  effects,  effacing  the  moral  sense  as 
it  effaces  the  memory  sometimes,  and  one  of  the  most  striking  phe- 
nomena observed  in  asylums  is  the  extreme  change  in  the  moral 
character  in  the  epileptic  which  precedes  and  heralds  the  approach 
of  his  fits.  A  fever  or  an  injury  to  the  head  has,  in  like  manner, 
transformed  the  moral  character." 

Passing  this  subject  by  for  the  present,  it  is  clear  that,  consciously 
or  unconsciously,  arbitrarily  or  naturally,  freely  or  of  necessity,  every 
living  thing  responds  to  some  part  of  the  order  of  nature,  and  that 
the  study  of  this  order  is  part  of  biology ;  for  there  are  many 
reasons,  besides  those  we  have  considered,  why  the  biologist  should 
have  peculiar  interest  in  the  principles  of  science.  His  studies  bring 
him  into  intimate  contact  with  certain  conceptions  which  play  such  a 


INTRODUCTORY  2$ 

subordinate  part  in  the  other  sciences  that  it  falls  to  him  to  assert 
their  importance,  since  they  are  so  little  regarded  outside  his  circle 
that  students  in  other  lines  often  fail  to  catch  what  he  has  in  mind. 
Among  these  are  the  principle  of  genetic  continuity  and  the  prin- 
ciple of  iitness,  with  all  that  they  imply.  For  all  I  know  to  the 
contrary,  the  principle  of  fitness  may  be  universal,  and  the  order 
of  nature  may  be  the  order  of  fitness ;  and  again,  for  all  I  know  to 
the  contrary,  all  significant  resemblances  between  the  phenomena  of 
nature  may  be  due  to  genetic  continuity ;  but,  at  the  present  day, 
these  principles  hold  no  prominent  place  in  the  minds  of  those  who 
deal  with  the  not-living,  and  their  introduction  among  the  principles 
of  science  is  due  to  the  biologists.  Now  only  a  moment's  thought 
is  needed  to  discover  how  great  are  the  difficulties  that  attend  the 
application  of  these  principles.  What  do  we  mean  by  the  genetic 
continuity  of  life .''  How  are  we  to  interpret  the  facts  of  embryology  ? 
How  many  perplexing  intricacies  face  us  if  we  undertake,  with 
William  Harvey,  "to  seek  the  truth  regarding  the  following  difficult 
questions :  Which  and  what  principle  is  it  whence  motion  and 
generation  proceed .''  Whether  is  that  which  in  the  egg  is  cause, 
artificer,  and  principle  of  generation,  and  of  all  the  vital  and 
vegetative  operations,  —  conservation,  nutrition,  growth,  —  innate  or 
superadded .''  and  whether  does  it  inhere  primarily,  of  itself,  and  as 
a  kind  of  nature,  or  intervene  by  accident,  as  a  physician  in  curing 
disease .''  Whether  is  that  which  transfers  an  egg  into  a  pullet 
inherent  or  acquired  .-*  " 

"  In  truth,"  says  Harvey,  "  there  is  no  proposition  more  mag- 
nificent to  investigate  or  more  useful  to  ascertain  than  this :  How 
are  all  things  formed  by  an  univocal  agent .''  How  does  the  like 
ever  generate  its  like  .''  Why  may  not  the  thoughts,  opinions,  and 
manners  now  prevalent,  many  years  hence  return  again,  after  an 
intermediate  period  of  neglect  .■'  "  ^ 

As  we  find  embryologists,  two  hundred  and  fifty  years  after  these 
words  were  written,  still  vexing  themselves  over  the  question,  — 
Whether  is  that  which  transfers  an  egg  into  a  pullet  inherent  or 
acquired.''  —  it  is  clear  that  we  cannot  hope  for  much  progress  in  the 
investigation  of  this  magnificent  proposition  unless  we  can  deter- 
mine what  we  mean  by  that  metaphysical  notion,  inherent  potency. 

^  Harvey,  "  De  Generatione,"  pp.  274-582. 


24  THE  FOUNDATIONS   OF  ZOOLOGY 

"  By  way  of  escape  from  the  metaphysical  Will-o'-the-Wisps 
generated  in  the  marshes  of  literature  and  theology,  the  serious 
student  is  sometimes  bidden,"  says  Huxley,  "  to  betake  himself  to 
the  solid  ground  of  physical  science.  But  the  fish  of  immortal 
memory,  who  threw  himself  out  of  the  frying-pan  into  the  fire, 
was  not  more  ill  advised  than  the  man  who  seeks  sanctuary  from 
philosophical  persecution  within  the  walls  of  the  observatory  or 
the  laboratory ;  for  metaphysical  speculation  follows  as  closely 
upon  physical  theory  as  black  care  upon  the  horseman."  ^ 

If,  as  modest  biologists,  we  were  to  assert  that  the  biological 
aspects  of  the  physical  sciences  are  the  only  basis  for  rational 
interest  in  these  sciences,  our  good  friends  in  physical  and  chemical 
laboratories  would,  no  doubt,  charge  us  with  arrogance,  although 
I  think  they  must  admit  that  the  principles  of  science,  as  dis- 
tinguished from  the  concrete  sciences,  are  part  of  biology. 

We  cannot  investigate  response  to  the  order  of  nature  without 
asking  what  the  order  of  nature  is.  What  are  the  properties  of 
things  and  of  thought  that  convince  us  of  its  existence .-'  What  is 
this  conviction  worth .-"  What  are  the  methods  by  which  knowledge 
of  this  order  is  acquired  and  perfected  and  extended  .-*  How  far 
are  these  methods  and  instruments  trustworthy .''  Are  any  limits 
to  their  application  known,  and,  if  so,  how  known .? 

To  all  these  questions  the  zoologist  has  a  peculiar  right  to  ask 
answers,  in  addition  to  the  right  which  he  shares  with  other  stu- 
dents of  science. 

"The  Mind,  her  acts  and  faculties,"  says  Berkeley,  "furnish  a 
new  and  distinct  class  of  objects,  from  the  contemplation  whereof 
arise  other  notions,  principles,  and  verities.  It  may  therefore  be 
pardoned  if  this  rude  essay  doth,  by  insensible  transitions,  draw 
the  reader  into  remote  inquiries  and  speculations,  that  were  not, 
perhaps,  thought  of  either  by  him  or  by  the  author  at  first  setting 
out." 

Some,  who  believe  they  at  least  are  rigorously  scientific,  may 
here  feel  impelled  to  cry  out  that  these  inquiries  are  not  scientific, 
but  metaphysical,  and  that  modern  men  of  science  have  nothing 
to  do  with  them.  For  my  own  part,  I  might  be  disposed  to  agree 
with   them    if   the    average    human    mind    were,    on   these    difficult 

^  Huxley,  VI.,  p.  200. 


INTRODUCTORY  25 

matters,  a  tabula  rasa;  but  ignorance  and  prejudice  and  education 
all  conspire  to  predispose  us  to  some  form  of  a  priori  philosophy, 
and  most  men  who  have  not  given  hard  thought  to  the  subject 
hold  fast,  consciously  or  unconsciously,  to  belief  in  the  universal 
and  necessary  conservation  of  energy,  to  belief  in  a  necessary  law 
of  universal  progress  or  evolution,  to  belief  in  the  arbitrary  and 
absolute  freedom  of  the  will,  or  to  belief  in  some  other  a  priori 
notion  which  they  hold  necessary  and  ultimate,  or  arbitrary  and 
absolute. 

"The  maxim  that  metaphysical  inquiries  are  barren  of  result," 
says  Huxley,  "and  that  the  serious  occupation  of  the  mind  with 
them  is  a  mere  waste  of  time  and  labor,  finds  much  favor  in  the 
eyes  of  many  persons  who  pride  themselves  on  the  possession  of 
sound  common  sense ;  and  we  sometimes  hear  it  enunciated  by 
weighty  authorities,  as  if  its  natural  consequence,  the  suppression 
of  such  studies,  had  the  force  of  a  moral  obligation." 

"  In  this  case,  however,  as  in  so  many  others,  those  who  lay 
down  the  law  seem  to  forget  that  a  wise  legislator  will  consider, 
not  merely  whether  his  proposed  enactment  is  desirable,  but  whether 
obedience  to  it  is  possible.  For  if  the  latter  question  be  answered 
negatively,  the  former  is  surely  hardly  worth  debate." 

"  Here,  in  fact,  lies  the  pith  of  the  reply  to  those  who  would 
make  metaphysics  contraband  of  intellect.  Whether  it  is  desirable  to 
place  a  prohibitory  duty  upon  philosophical  speculations  or  not,  it  is 
utterly  impossible  to  prevent  the  importation  of  them  into  the  mind. 
And  it  is  not  a  little  curious  to  observe  that  those  who  most  loudly 
profess  to  abstain  from  such  commodities  are,  all  the  while,  uncon- 
scious consumers,  on  a  great  scale,  of  one  or  another  of  their  mul- 
titudinous disguises  or  adulterations.  With  mouths  full  of  the 
particular  kind  of  heavily  buttered  toast  which  they  affect,  they 
inveigh  against  the  eating  of  plain  bread.  In  truth,  the  attempt  to 
nourish  the  human  intellect  upon  a  diet  which  contains  no  meta- 
physics is  about  as  hopeful  as  that  of  certain  Eastern  sages  to 
nourish  their  bodies  without  destroying  life." 

"  Everybody  has  heard  the  story  of  the  pitiless  microscopist,  who 
ruined  the  peace  of  mind  of  one  of  these  mild  enthusiasts  by  show- 
ing him  the  animals  moving  in  a  drop  of  the  water  with  which,  in 
the  innocency  of  his  heart,  he  slaked  his  thirst ;  and  the  unsuspect- 


26  THE  FOUNDATION'S  OF  ZOOLOGY 

ing  devotee  of  plain  common  sense  may  look  for  as  unexpected  a 
shock  when  the  magnifier  of  severe  logic  reveals  the  germs,  if  not 
the  full-grown  shapes,  of  lively  metaphysical  postulates  rampant 
amidst  his  most  positive  and  matter  of  fact  notions."  ^ 

Kant  has  shown,  as  Berkeley  showed  before  him,  that,  instead  of 
discovering  truth,  philosophy  has  only  the  modest  merit  of  preventing 
error,  and  if  men  never  made  mistakes,  but  always  reasoned  wisely 
and  acted  rightly,  we  should  little  need  to  study  the  nature  of  know- 
ledge ;  but  while  few  men  think,  all  have  opinions ;  and  there  are 
certain  perennial  errors,  idols,  as  Bacon  calls  them,  which  find  in  the 
mind  of  man  a  dwelling-place  so  congenial  that  the  doctrine  of  idols 
bears  the  same  relation  to  the  interpretation  of  nature  as  that  of 
sophisms  does  to  common  logic. 

As  we  are  forced,  by  the  imperfection  of  our  nature,  to  study  the 
principles  of  knowledge  in  order  to  guard  ourselves  from  error,  it 
makes  little  difference  whether  we  call  the  principles  of  science 
metaphysical  or  not. 

We  speak  of  physical  science,  but  it  would  surely  be  more  repug- 
nant to  the  usage  of  common  speech  to  call  the  principles  of  science 
physical  than  to  call  them  metaphysical ;  for,  while  the  data  of 
science  are  things  known  to  sense,  we  must  ask,  with  Berkeley, 
whether  it  is  not  certain  that  the  principles  of  science  are  neither 
objects  of  sense  nor  of  the  imagination  ;  whether  they  do  not  arise 
in  the  mind  itself ;  whether  the  sensible  world  is  anything  more  than 
the  stimulus  which  calls  forth  the  innate  or  latent  powers  of  the 
mind.  We  assuredly  have  no  sense-organ  by  which  a  principle  may 
be  perceived,  except  so  far  as  we  have  by  nature  an  organ  of  com- 
mon sense.  If  the  principles  of  science  are  perceived  at  all,  rather 
than  apprehended,  they  must  be  perceived  by  some  inner  sense,  for 
which  we  know  no  sense-organ. 

"  As  understanding  perceiveth  not,  that  is,  doth  not  hear,  or  see, 
or  feel,  so  sense  knoweth  not ;  and  although  the  mind  may  use 
both  sense  and  fancy,  as  means  whereby  to  arrive  at  knowledge, 
yet  sense  or  soul,  so  far  forth  as  sensitive,  knoweth  nothing.  For, 
as  it  is  rightly  observed  in  the  *  Theaetetus '  of  Plato,  science  con- 
sisteth  not  in  the  passive  perceptions,  but  in  the  reasoning  about 
them." 

1  Huxley,  "  Collected  Essays,"  VI.,  pp.  288,  289. 


INTRODUCTORY  2J 

Some,  who  so  far  agree  with  Plato,  may  be  led  to  remind  Berke- 
ley that  objects  of  sense  are  not  only  first  considered  by  all  men,  but 
most  considered  by  most  men ;  and  that  the  possession  of  opinions 
may  be  no  evidence  of  reason. 

Truth,  he  tells  us,  is  the  cry  of  all,  but  the  game  of  few ;  and 
while  there  may  be  wisdom  in  a  multitude  of  counsellors,  Huxley 
reminds  us  that  it  is  in  but  one  or  two  of  them. 

Some  may  assert  that,  admitting  that  we  have  no  sense-organ 
by  which  we  perceive  the  relation  between  a  pattering  sound  on 
the  roof  and  a  shower,  the  connection  between  the  sound  of  rain 
and  the  falling  drops  is  nevertheless  physical  and  not  mental ; 
and  that  response  to  the  order  of  nature  is  no  evidence  of  reason, 
since  we  do  not  attribute  judgment  to  the  mimosa,  which,  stimu- 
lated by  the  falling  drops,  folds  its  leaves  that  the  rain  may  reach 
its  roots. 

They  may  also  assert  that,  if  the  structure  and  history  of  all 
parts  of  our  own  organic  mechanism  were  fully  known,  we  should 
be  able  to  show  that  the  principles  of  science  are  physical ;  that 
we  apprehend  them  because  our  minds  are  the  ones  which  have 
survived  the  struggle  for  existence ;  and  that  these  principles  are 
no  more  than  natural  selection  would  lead  one  to  expect ;  although 
we  must  ask  whether  we  find  in  nature  any  reason  why  what 
we  expect  must  happen  ;  whether  natural  selection  is  an  efficient 
cause,  or  only  a  generalization  from  experience ;  and  whether 
experience  is  not  itself  a  state  of  mind.  We  may  point  out  that 
hope  is  not  science,  and  that  no  one  has,  as  yet,  deduced  the 
principles  of  science  from  brain  anatomy ;  and  we  may  ask  whether, 
if  this  were  accomplished,  the  anatomical  structure  of  the  brain, 
and  of  the  other  organs  which  we  study  by  our  senses,  is  not  a 
thing  perceived ;  whether  perception  is  not  mental ;  and  whether 
a  thing  perceived  by  sense  is  not  a  phenomenon  of  mind.  We 
may  also  ask  whether  proof  that  our  organ  of  common  sense  has 
come  about,  like  our  eyes  and  ears,  by  the  survival  of  the  fittest^ 
would  tell  us  any  more  about  the  relation  between  mind  and 
matter  than  our  eyes  and  ears  tell  us  now. 

I  am  not  able  to  answer  the  question  whether,  in  ultimate 
analysis,  the  principles  of  science  are  physical  or  metaphysical. 
I   know  nothing  about  things   ultimate.     I  do  not   know  what  the 


28  THE  FOUNDATIONS  OF  ZOOLOGY 

relation  between  mind  and  matter  is.  I  do  not  know  whether 
the  distinction  between  "things  perceived  by  sense"  and  "rela- 
tions apprehended  by  the  mind"  is  founded  in  nature  or  not; 
but  I  am  sure  that  natural  knowledge  is  useful  to  me,  that  it  is 
pleasant,  and  profitable,  and  instructive ;  and  I  must  ask  whether 
all  this  does  not  show  that  nature  is  intended. 

This  introductory  summary  of  some  of  the  topics  I  shall  try 
to  handle  in  the  following  lectures  shows  that  these  topics  are 
neither  few  nor  simple,  nor  am  I  so  bold  as  to  think  that  I  can 
set  any  one  of  them  on  a  firm  foundation ;  for,  like  William 
Harvey,  I  do  not  wish  what  I  say  "  to  be  taken  as  if  I  thought 
it  a  voice  from  an  oracle  "  ;  although  I  hope  it  may  "  stir  up  the 
intellects  of  the  studious  to  search  more  deeply  into  so  obscure 
a  subject." 

I  shall  make  no  attempt  at  originality,  but  shall  try  to  give 
you  some  of  the  results  of  my  own  study  of  the  thoughts  of 
others.  Bacon  tells  us  indeed  that  it  is  seldom  in  our  power  to 
both  admire  and  surpass  our  author;  since,  like  water,  we  rise 
not  higher  than  the  springhead  whence  we  have  descended ;  but 
I  cannot  agree  with  him  that  the  attempt  to  put  the  thoughts  of 
others  in  a  new  dress  necessarily  leads  to  the  great  injury  of 
learning,  for  we  often  fail  to  master  the  wise  thoughts  of  one 
who  is  not  of  our  own  times  because  his  turn  of  words  does  not 
fit  our  point  of  view. 

All  I  have  to  say  is  anticipated  in  invention  and  is  varied  only 
by  the  method  of  treating  it.  "  For,"  like  Montaigne,  "  I  make 
others  to  relate  (not  after  my  own  fantastie,  but  as  it  best  falleth  out) 
what  I  cannot  so  well  express,  either  through  unskill  of  language 
or  want  of  judgement.  I  number  not  my  borrowings,  but  I  weigh 
them.  And  if  I  w^ould  have  made  their  number  to  prevail,  I 
would  have  had  twice  as  many."  But  I  trust  that.  Bacon  notwith- 
standing, I  have  neither  corrupted  the  labors  of  my  predecessors 
nor  contributed  to  the  slavery  of  the  sciences. 

The  lectures  which  follow  have  been  prepared  at  different 
times,  and  for  various  reasons ;  but  I  hope  that,  as  I  have  arranged 
them,  they  will  exhibit  unity  of  purpose,  and  the  logical  develop- 
ment of  that  purpose,  which,  in  a  word,  is  this :  To  show  to  them 
who   think   with    Berkeley,    that    "  it   is   a   hard   thing   to   suppose 


INTRODUCTORY  29 

that  right  deductions  from  true  principles  should  ever  end  in 
consequences  which  cannot  be  maintained  or  made  consistent," 
that,  in  my  opinion,  there  is  nothing  in  the  prevalence  of  mechani- 
cal conceptions  of  life,  and  of  mind,  or  in  the  unlimited  exten- 
sion of  these  conceptions,  to  show  that  this  hard  thing  to  suppose 
is  true. 


LECTURE    II 

HUXLEY,   AND  THE  PROBLEM   OF 
THE   NATURALIST 


LECTURE    IP 

HUXLEY,  AND   THE   PROBLEM   OF  THE  NATURALIST 

All  thoughtful  students  will  prize  the  essays  and  addresses  on 
Education  which  make  up  the  third  volume  of  Huxley's  "  Collected 
Essays."  When  written,  these  were  regarded  by  most  readers  as 
special  pleas  for  scientific  education  ;  but  nothing  could  be  farther 
from  the  truth,  although  the  prominence  of  "science"  in  their  titles 
gives  some  ground  for  this  impression.  They  who  read  them  now, 
after  scientific  education  has  become  an  assured  fact,  will  find  that 
Huxley  shows,  here  as  elsewhere,  that  he  is  no  radical,  seeking  to 
sweep  away  the  ancient  landmarks,  but  an  enthusiastic  admirer  of 
all  that  is  good  in  the  old,  as  well  as  a  zealous  advocate  for  the  new 
in  education. 

While  he  improves  every  opportunity  to  set  forth  the  need  for 
scientific  education,  he  tells  the  student  that  he  is  a  man  and  a  citizen 
as  well  as  a  student ;  and  the  delights  and  the  discipline  of  literature 
and  art  and  history  are  emphasized  again  and  again,  and  each  essay 
is  a  plea  for  liberal  culture  ;  although  he  never  fails  to  demand  the 
removal  of  the  accumulated  ashes,  and  the  rekindling  of  the  pure 
flame,  until  the  very  air  the  student  breathes  shall  become  "  charged 
with  that  enthusiasm  for  truth,  that  fanaticism  of  veracity,  which 
is  a  greater  possession  than  much  learning ;  a  nobler  gift  than  the 
power  of  increasing  knowledge." 

No  one  —  Huxley  least  of  all  —  would  dream  of  attributing  the 
"  New  Reformation  "  to  any  one  man,  and  he  speaks  of  himself 
as  "a  full  private  who  has  seen  a  good  deal  of  service  in  the  ranks  " 
of  the  army  ranged  around  the  banner  of  physical  science ;  but  the 
object  to  which  he  tells  us  he  has  devoted  his  life  —  the  diffusion 
among  men  of  the  scientific  spirit  of  "organized  common  sense"  — 

1  This  lecture  is  part  of  a  Review  of  Huxley's  Essays,  which  was  printed  in  the  Forum, 
November,  1895. 


34  THE  FOUNDATIONS   OF  ZOOLOGY 

has  made  notable  progress  during  his  lifetime,  and  in  this  assurance  he 
tells  us  at  its  end  that  he  "shall  be  content  to  be  remembered,  or  even 
not  remembered,"  as  one  among  the  many  who  have  brought  it  about. 

Of  all  Huxley's  essays,  those  which  deal  with  the  development 
rather  than  the  application  of  the  method  of  using  one's  reason 
rightly  in  the  search  for  truth  are  of  most  value  to  the  student. 
Among  them  are  the  whole  of  Volume  VI.,  "Hume;  with  Helps 
to  the  Study  of  Berkeley"  ;  as  well  as  the  one  "On  Descartes'  Dis- 
course Touching  the  Method  of  Using  our  Reason  Rightly ;  and 
of  Seeking  Scientific  Truth  "  (I.  iv.),  and  many  others,  such  as 
"Possibilities  and  Impossibilities"  (V.  vi.  1891),  and  "Scientific 
and  Pseudo-Scientific  Realism  "  (V.  ii.  1887). 

The  opening  paragraph  of  the  book  on  Hume's  Philosophy  (VI.  57) 
may  be  taken  as  a  statement  of  the  purpose  of  all  these  essays  : 
"  Kant  has  said  that  the  business  of  philosophy  is  to  answer 
three  questions  :  What  can  I  know  .''  —  What  ought  I  to  do  .^  —  and. 
For  what  may  I  hope .-'  But  it  is  pretty  plain  that  these  three 
resolve  themselves  in  the  long  run  into  the  first.  For  rational 
expectation  and  moral  action  are  alike  based  upon  belief,  and  a 
belief  is  void  of  justification  unless  its  subject-matter  lies  within  the 
boundaries  of  possible  knowledge,  and  unless  its  evidence  satisfies 
the  conditions  of  credibility.  .  .  .  Fundamentally,  then,  philosophy 
is  the  answer  to  the  question,  What  can  I  know  .-•  " 

Huxley  is  not  drawn  into  this  province  by  the  fierce  joy  of  con- 
troversy, nor  by  any  desire  to  join  those  who  flit  forever  over  dusky 
meadows,  green  with  asphodel,  in  vain  search  for  some  reality  which 
is  not  within  the  reach  of  all.  His  motive  is  the  most  practical  and 
serious  one  we  know,  —  "  to  learn  what  is  true  in  order  to  do  what 
is  right."  This,  he  tells  us,  "is  the  summing  up  of  the  whole  duty 
of  man,  for  all  who  are  not  able  to  satisfy  their  mental  hunger  with 
the  east  wind  of  authority."  The  conclusion  of  the  whole  matter 
is  that  "  there  is  but  one  kind  of  knowledge  and  but  one  method 
of  acquiring  it."  This  is  the  melody  which  runs  through  all  the 
nine  volumes ;  now  loud  and  clear,  now  hidden  by  the  minor  inter- 
est of  a  scientific  topic,  or  by  the  heat  of  controversy  or  by  the 
charm  of  literary  genius;  but  always  present,  and  easy  —  for  one 
who  listens  —  to  detect.  It  is  because  scientific  education  helps 
us  to  acquire  the  method  of  using  our  reason  rightly  in  the  search 


HUXLEY,  AND   THE  PROBLEM  OF  THE  NATURALIST       35 

for  truth,  and  not  because  science  is  the  one  thing  worth  knowing, 
that  he  pleads  for  it  so  eloquently.  It  is  because  the  improvement 
of  natural  knowledge  is  conclusive  testimony  to  the  value  of  this 
method  that  he  devoted  his  life  to  the  popularization  of  science. 
It  is  because  his  right  to  use  this  method  —  the  right  which  is  also 
the  highest  and  first  of  duties  —  was  disputed,  that  he  entered  the 
stormy  waters  of  controversy. 

"  If  I  may  speak  of  the  objects  I  have  had  more  or  less  definitely 
in  view,  .  .  .  they  are  briefly  these  ;  To  promote  the  increase  of 
natural  knpwledge,  and  to  forward  the  application  of  scientific 
methods  to  all  the  problems  of  life,  to  the  best  of  my  ability,  in 
the  conviction,  which  has  grown  with  my  growth  and  strengthened 
with  my  strength,  that  there  is  no  alleviation  for  the  sufferings  of 
mankind  except  veracity  of  thought  and  action,  and  the  resolute 
facing  of  the  world  as  it  is  when  the  garment  of  make-believe  with 
which  pious  hands  have  hidden  its  uglier  features  is  stripped  off." 

To  what  nobler  end  could  life  be  devoted  than  the  attempt  to 
show  us  how  we  may  "  learn  to  distinguish  truth  from  falsehood,  in 
order  to  be  clear  about  our  actions,  and  to  walk  surefootedly  in  this 
life  "  }  If  he  has  succeeded,  and  every  zoologist  who  is  free  to  fol- 
low Nature  wherever  she  may  lead  is  a  witness  that  he  has  suc- 
ceeded,—  if,  as  the  end  of  his  lifelong  labor,  intellectual  freedom 
is  established  on  a  firmer  basis, — this  is  his  best  monument,  even 
if  the  man  should  quickly  be  forgotten  in  the  accomplishment  of  his 
end.  No  memorial  could  be  more  appropriate  than  the  speedy 
establishment  of  that  intellectual  liberty  which  is  not  intellectual 
license  on  a  basis  so  firm  that  the  history  of  the  struggle  to  obtain 
it  shall  become  a  forgotten  antiquity. 

Huxley's  lifelong  devotion  to  the  task  of  teaching  the  right 
method  of  using  our  reason  in  the  search  for  truth  has  been  so 
fruitful  that  the  success  or  failure  of  his  attempts  to  teach  the 
application  of  this  method  to  specific  problems  is  a  matter  of  very 
subordinate  importance. 

As  he  was  not  only  a  man  and  a  citizen,  but,  above  all,  a  natu- 
ralist, peculiar  interest  attaches  to  his  utterances  on  the  problems 
of  biology,  although  his  various  essays  on  this  subject  differ  so 
much  in  perspective  that  their  effect  upon  many  thoughtful  readers 
has  proved  to  be  practically  equivalent  to  inconsistency.     It  is  easy 


36  THE  FOUNDATIONS   OF  ZOOLOGY 

to  show  that,  in  this  case,  as  in  others,  the  responsibility  rests 
with  the  reader  and  not  with  the  author ;  but,  however  this  may 
be,  the  opinion  that  his  utterances  are  inconsistent  is  real  and 
therefore  a  proper  subject  for  examination.  Huxley's  frame  of 
mind  in  1854  is  embodied  in  the  essay  "On  the  Educational  Value 
of  the  Natural  History  Sciences  "  (HI.  ii.),  from  which  I  copy  the 
following  passage  (p.  43):  — 

"  What  is  the  cause  of  this  wonderful  difference  between  the 
dead  particles  and  the  living  particles  of  matter  appearing  in  other 
respects  identical?  —  that  difference  to  which  we  give  the  name  of 
life  ?  I,  for  one,  cannot  tell  you.  It  may  be  that  by  and  by 
philosophers  will  discover  some  higher  laws  of  which  the  facts  of 
life  are  particular  cases,  —  very  possibly  they  will  find  out  some 
bond  between  physico-chemical  phenomena  on  the  one  hand  and 
vital  phenomena  on  the  other.  At  present,  however,  we  assuredly 
know  of  none  ;  and  I  think  we  shall  exercise  a  wise  humility  in 
confessing  that  for  us,  at  least,  ,  .  .  this  spontaneity  of  action  .  .  . 
which  constitutes  so  vast  and  plain  a  distinction  between  living 
bodies  and  those  which  do  not  live  is  an  ultimate  fact :  indicating, 
as  such,  the  existence  of  a  broad  line  of  demarcation  between  the 
subject-matter  of  biological  and  that  of  all  other  sciences." 

Between  1854  and  the  publication  of  the  essay  "On  the  Physical 
Basis  of  Life"  in  1868,  natural  science  advanced  with  strides  which 
have  no  parallel,  and  the  "  Origin  of  Species "  brought  about  a 
revolution  in  our  conceptions  of  the  history  of  living  nature.  It 
is  not  surprising  that  Huxley's  point  of  view  undergoes  significant 
change,  and  that  a  new  aspect  of  nature  now  excites  his  interest 
and  absorbs  his  attention.  The  establishment  of  the  doctrine  of 
the  continuity  of  life  on  a  firm  basis,  and  the  acceptance  of  the 
generalization  that  all  living  things  are  related  by  birth,  had  given 
new  meaning  to  the  familiar  truth  that  they  are  all  fundamentally 
identical  in  structure  ;  and  the  essay  of  1868  deals  with  this  aspect 
of  living  organisms.  The  essay  is  regarded  by  many  readers  — 
both  those  who  look  upon  it  with  horror  and  those  who  make  it 
the  basis  of  a  biological  creed — as  contradictory  to  the  essay  of 
1854;  but  I,  for  one,  am  unable  to  find  in  it  any  basis  for  this 
opinion.  Its  motive  —  the  truth  that  "protoplasm  is  the  basis  of 
life";  that  "it  is  the  clay  of  the  potter,  which,  bake  it  and  paint 


HUXLEV,   AND   THE  PROBLEM  OF  THE  NATURALIST       37 

it  as  he  will,  remains  clay,  separated  by  artifice  and  not  by  nature 
from  the  commonest  brick  or  sundried  clod,"  is  no  novelty.  In 
fact,  the  essay  is  nothing  more  than  a  statement  in  modern 
terms  of  the  new  evidence  which  modern  science  furnishes  in  con- 
firmation of  the  familiar  conviction  that,  so  far  as  his  physical 
basis  is  concerned,  man  hath  no  preeminence  above  the  beasts ; 
that  they  all  have  one  breath  ;  that  is,  the  rain  on  the  earth  which 
causes  the  bud  of  the  tender  herb  to  spring  forth  ;  that  as  for  the 
earth,  it  giveth  us  bread ;  that  the  vital  spark  is  soon  quenched 
unless  it  is  kept  alive  by  fuel  from  without ;  that  the  living  machine 
must  soon  break  down  and  wear  out ;  and  that  then  shall  return 
the  dust  to  the  earth  as  it  was.  Huxley  says  :  "  Past  experience 
leads  me  to  be  tolerably  certain  that  when  the  propositions  I  have 
just  placed  before  you  are  accessible  to  public  comment  and  criti- 
cism they  will  be  condemned  by  many  zealous  persons,  and  perhaps 
by  some  few  of  the  wise  and  thoughtful."  They  who  remember 
the  reception  of  the  essay  are  aware  that  this  expectation  was  not 
disappointed,  but  it  is  hard  to  understand  why  ;  for  its  substance, 
if  not  its  modern  language,  has  been  the  common  property  of 
some  of  the  wise  and  thoughtful  for  ages. 

I  do  not  see  why  any  one  should  challenge  Huxley's  statement 
that  "it  seems  to  me  that  we  are  logically  bound  to  apply  to 
protoplasm  or  the  physical  basis  of  life  the  same  conceptions 
which  are  held  to  be  legitimate  elsewhere.  If  the  phenomena 
exhibited  by  water  are  its  properties,  so  are  those  presented  by 
protoplasm  its  properties."  We  may  have  practical  objections, 
based  on  expediency  and  not  on  logic,  to  the  further  statement 
that  "we  live  in  the  hope  and  in  the  faith  that  by  the  advance  of 
molecular  physics  we  shall,  by  and  by,  be  able  to  see  our  way  as 
clearly  from  the  constituents  of  water  to  the  properties  of  water  as 
we  are  now  able  to  deduce  the  operation  of  a  watch  from  the  form  of 
its  parts  and  the  way  they  are  put  together."  Faith  and  hope  are 
good  things  no  doubt,  and  "expectation  is  permissible  when  belief  is 
not  "(VIII.  1870);  but  experience  teaches  that  the  expectation  or 
faith  of  the  master  is  very  apt  to  become  belief  in  the  mind  of  the 
student,  and  "science  warns  us  that  the  assertion  which  outstrips 
evidence  is  not  only  a  blunder,  but  a  crime."  (III.,  IV.,  150,  1880). 
In   order  to  avoid  all  danger  of  adding  to  the  criminal   classes  it 


38  THE  FOUyDATIONS  OF  ZOOLOGY 

is  perhaps  as  well  for  those  who  are  teachers  to  keep  their  faith 
outside  the  laboratory  as  much  as  possible. 

With  this  qualification  I  have  nothing  but  approval  for  the  pas- 
sage quoted,  as  well  as  for  the  rest  of  the  essay.  Like  Huxley,  I 
hold  that  we  are  logically  bound  to  apply  to  protoplasm  the  same 
conceptions  as  those  which  are  held  to  be  legitimate  elsewhere. 
Without  believing,  I  certainly  see  no  reason  for  doubting  that  all 
the  properties  of  organisms  may  possibly  be  some  day  deduced  from 
the  nature  and  disposition  of  their  constituent  molecules.  If  I 
should  live  to  see  this  proved,  I  should  believe  it  without  remodel- 
ling any  beliefs  I  now  hold  ;  for  most  assuredly  I  do  not  believe 
that  these  activities  are  the  result  of  anything  else  than  physical 
structure.  I  simply  do  not  know,  and  have  no  belief  whatever  on 
the  subject,  although  I  welcome  every  addition  to  our  knowledge 
of  the  properties  of  the  physical  basis  of  life,  in  the  conviction  that 
this  knowledge  is  a  necessary  condition  for  progress.  I  must  also 
insist,  however,  that  nothing  seems  more  obvious  to  me  than  that 
we  might  study  the  form  of  the  parts  of  a  watch,  and  the  way  they 
are  put  together,  till  the  crack  of  doom,  without  understanding  it 
in  any  sense  worthy  the  name.  To  understand  it  we  must  study 
not  only  its  mechanism  and  the  movements  to  be  deduced  from  it, 
but  the  movements  of  the  earth  as  well ;  and  then  we  must  study 
a  third  thing,  —  that  relation  between  the  two  which  fits  a  watch  for 
man's  service.  I  hold  that,  in  this  sense  of  the  word,  we  can 
"understand"  watches,  and  that  good  common  sense  forces  us  to 
admit  not  only  that  the  fitness  of  a  watch  is  real,  but  that  it  is  the 
only  basis  for  rational  interest  in  watches.  Analogies  are  dangerous 
weapons,  because  of  our  fondness  for  pushing  them  farther  than 
the  facts  warrant,  and  for  assuming  that  resemblance  in  one  feature 
involves  resemblance  in  other  features.  The  fact  that  living  things 
are  like  watches  in  their  fitness,  in  their  adjustment  to  the  phe- 
nomena of  the  external  world,  at  once  suggests  many  interesting 
questions  with  which  I  have  no  intention  to  deal  at  present.  This 
particular  resemblance  is  obvious,  and  I  hold  that  whatever  may 
be  possible  to  the  zoologist  of  future  ages,  the  only  method  of  study- 
ing this  fitness  which  is  available  at  the  present  day  is  like  that 
which  we  apply  to  watches. 

Huxley  says  :  "  If  the  properties  of  water  may  be  properly  said 


HUXLEY,   AND    THE  PROBLEM  OF  THE  NATURALIST       39 

to  result  from  the  nature  and  disposition  of  its  component  molecules, 
I  can  find  no  intelligible  ground  for  refusing  to  say  that  the  prop- 
erties of  protoplasm  result  from  the  nature  and  disposition  of  its 
molecules." 

I  know  no  reason  why  any  one  should  "refuse  to  say"  this, 
except  that  "the  assertion  which  outstrips  evidence  is  a  crime." 
When  it  has  been  proved,  I,  for  one,  shall  say  it  cheerfully  ;  but  I 
cannot  forget  that  we  have  been  taught  for  two  thousand  years  and 
more  that  life  is  not  a  property  of  the  physical  basis  like  the  prop- 
erties of  water,  but  a  relation,  an  adjustment  between  the  properties 
of  the  organism  and  of  those  of  the  environment,  between  the 
changes  which  take  place  in  the  body  and  those  which  go  on  in  the 
world  around  it;  that  this  adjustment  serves  to  promote  the  welfare 
of  the  species,  and  that  we  know  nothing  comparable  to  it  in  water 
or  in  anything  else  except  living  beings,  and  their  products,  such 
as  watches,  and  spiders'  webs,  and  birds'  nests. 

The  author  of  our  oldest  book  on  zoology  opens  it  with  the 
following  statement  of  its  purpose  :  — 

"To  say  what  are  the  ultimate  substances  out  of  which  an  animal 
is  formed  ...  is  no  more  sufficient  than  would  be  a  similar  account 
in  the  case  of  a  couch.  For  we  should  not  be  content  with  saying 
that  the  couch  was  made  of  bronze  or  of  wood,  or  whatever  it  might 
be,  but  should  try  to  describe  its  design  or  mode  of  composition  in 
preference  to  the  material.  ...  It  is  plain  that  the  teaching  of 
the  old  physiologists  is  inadequate,  and  that  the  true  method  is  to 
state  what  the  definite  characters  are  that  distinguish  the  animal 
as  a  whole.  ...  In  fact,  to  proceed  in  exactly  the  same  way  as  we 
should  do  if  we  were  giving  a  complete  description  of  a  couch."  ^ 

If  this  is  true,  if  life  is  not  a  property  like  those  of  water,  but 
an  adjustment  between  properties,  it  must  be  clear  that  no  amount 
of  knowledge  of  any  properties  of  the  physical  basis  except  the 
property  of  fitness  can  ever  give  us  a  science  of  life,  although  it 
must  be  equally  clear  that  knowledge  of  all  its  properties  is  a 
necessary  condition  for  progress.  My  comment  on  the  essay  "  On 
the  Physical  Basis  of  Life "  is  that,  while  I  fully  agree  with  it, 
I  hold  with  Aristotle  that  it  is  "inadequate,"  although  I  am  quite 
prepared  to  admit  the  possibility  that  this  inadequacy  may  be  due 

1  Aristotle,  "  Parts  of  Animals,"  I.  i. 


40  THE  FOUNDATIONS  OF  ZOOLOGY 

to  my  own  limitations,  and  not  to  the  nature  of  the  subject.  While 
I  find  nothing  in  the  essay  which  need  give  any  one  a  moment's 
"  nightmare,"  I  am  equally  unable  to  find  in  it  any  warrant  except 
"faith"  for  the  dogma  that  biology  —  the  science  of  life  —  now  is, 
or  is  at  all  likely  soon  to  be,  the  study  of  the  physical  and  chemi- 
cal properties,  or  any  other  property  except  fitness,  of  the  physical 
basis. 

The  partial  failure  of  training  in  biological  laboratories  to  make 
naturalists  of  the  students,  or  to  excite  in  them  that  interest  in  the 
homes  of  living  things  which  has  so  often  proved  a  greater  delight 
than  art  or  literature ;  its  failure  to  stimulate  the  investigation  of 
those  relations,  between  animals  and  plants  and  the  world  around 
them  which  constitute  life, — has  begun  to  attract  attention  and  to 
excite  comment.  Among  the  many  reasons  assigned  for  this  failure 
"microtomes  "  have  occupied  a  prominent  place  and  have  been  held 
to  be  the  seat  of  the  mischief,  although  no  one  can  treat  seriously  the 
assertion  that  we  can  have  too  many  or  too  refined  means  for  research 
into  structure.  From  long  acquaintance  with  many  students  and  from 
much  discussion  with  them  I  have  satisfied  myself  that  the  belief 
that  our  biology  (the  biology  of  the  present  day,  and  not  that  of  the 
unknown  future)  ends  with  the  study  of  the  structure  and  functions 
of  the  physical  basis  —  the  belief  that  biology  is  "nothing  but" 
the  discovery  of  its  physical  and  chemical  properties  —  has  much 
to  do  with  it.  My  experience  also  tells  me  that  the  essay  "  On 
the  Physical  Basis  of  Life "  is  appealed  to  as  a  scientific  warrant 
for  this  belief,  although  we  have  seen  that  it  affirms  nothing  more 
than  a  "  hope  "  for  this  consummation. 

This  ground  was  all  worked  over  before  Aristotle's  day,  and 
perhaps  it  may  not  be  too  much  of  a  flight  of  the  imagination  to 
inquire  what  he  might  have  thought  of  this  essay.  Do  not  his 
reflections  in  the  "  Parts  of  Animals "  warrant  the  assertion  that 
his  comment  would  be  something  like  this  .-^  — 

"  Your  natural  science  interests  me  more  than  anything  else 
in  your  modern  world  ;  and  your  century  is  distinguished  beyond 
all  others  for  progress  in  the  history  of  life.  I  am  delighted  with 
this  essay,  and  no  other  pleasure  could  compare  with  that  which  I 
should  find  in  a  course  of  study  in  the  properties  of  living  things 
with  the  aid  of  your  appliances  for  research  ;  but  are  you  quite  sure 


HUXLEY,  AND   THE  PROBLEM  OF  THE  NATURALIST       4 1 

that  the  whole  case  is  stated  in  the  essay  ?  While  clay  is  the 
physical  basis  of  the  potter's  art,  its  essence  is  fitness  for  the  use 
of  man  :  and  what  concerns  us  is  not  that  he  uses  clay,  but  that 
he  makes  from  it  now  a  foundation-brick  and  now  an  ornamental 
coping ;  now  a  homely  kitchen  pot,  and  now  a  graceful  urn.  I 
have  studied  your  wonderful  chronometers  until  I  am  '  able  to 
deduce  the  operations  of  a  watch  from  the  form  of  its  parts  and 
the  way  they  are  put  together ' ;  but  I  failed  to  understand  them 
until  I  perceived  that  relation  between  their  movements  and  those 
of  the  earth  which  constitutes  their  fitness  for  man's  service.  I 
tried,  long  ago,  to  show  that  something  very  similar  is  true  of  living 
things.  We  may  sometime  be  able  to  foresee  or  deduce  all  their 
actions  from  their  structure,  but  at  present,  as  in  my  own  day,  the 
only  available  way  to  understand  them  is  to  study  their  relations 
to  the  world  around  them. 

"  My  teaching  that  the  essence  of  a  living  being  is  not  what  it 
is  made  of,  nor  what  it  does,  but  why  it  does  it,  has  been  rendered 
by  one  of  your  contemporaries  into  the  statement  that  life  is  the 
continuous  adjustment  between  internal  and  external  relations. 
If  this  is  true,  is  not  the  biology  which  restricts  itself  to  the  physical 
basis,  and  forgets  the  external  world,  like  your  play  of  '  Hamlet ' 
without  the  Hamlet .-'  Is  not  the  biological  laboratory  which  leaves 
out  the  ocean  and  the  mountains  and  meadows  a  monstrous  ab- 
surdity .''  Was  not  the  greatest  scientific  generalization  of  your 
times  reached  independently  by  two  men  who  were  eminent  in  their 
familiarity  with  living  things  in  their  homes .-' 

"  You  ask,  '  What  better  philosophical  status  has  vitality  than 
aquosity  .'^ ' — and  I  ask  you  in  turn  what  better  status  has  voli- 
tion than  vitality.^  —  yet  you  find  the  employment  of  this  word 
'both  useful  and  justifiable.'  You  can  separate  water  into  its 
elements  and  then,  by  recombining  them,  you  can  get  water  again  ; 
and  this  you  may  repeat  as  often  as  you  choose ;  but  can  you,  as 
yet,  do  anything  of  the  sort  with  living  things .''  When  by  the 
methods  of  the  laboratory  you  have  made  a  living  being ;  when 
you  have  made  not  merely  protoplasm,  —  nor  even  protoplasm  capa- 
ble of  nutrition,  growth,  reproduction,  and  contraction, — but  proto- 
plasm able  to  maintain  persistent  adjustment  to  the  shifting  world 
around    it,  —  then,   and    not    till    then,   will    I    admit   that  my  word 


42  THE  FOUNDATIONS   OF  ZOOLOGY 

*  vitality '  (yjrvx^e)  has  reached  the  end  of  its  long  career  of  useful- 
ness. 

"  I  admitted  long  ago  that  it  is  as  truly  a  property  of  a  bird  to 
build  a  nest  as  it  is  a  property  of  water  to  freeze ;  but  our  interest 
in  the  nest  lies  in  its  fitness  for  maintaining  the  species.  I  hear 
it  said  among  you  that  science  has  nothing  to  do  with  the  Why, 
but  only  with  the  How  ;  but  we  can  surely  give  answers  to  the 
questions  'Why  do  men  make  and  buy  watches?'  —  'Why  do 
birds    pursue   their   prey  ? '  —  '  Why    do  they   flee   their   enemies  ? ' 

—  and  'Why  do  they  make  nests?' — answers  which  are  good  and 
sensible,  although  they  are  incomplete. 

"The  naturalists  of  your  day  are  adding  continually  to  the 
overwhelming  evidence  for  a  truth  which  was  unsuspected  in  mine 

—  the  mutability  of  species  and  the  continuity  of  life.  If  I  could 
now  publish  a  new  edition  of  the  '  Parts  of  Animals,'  I  should 
treat  with  more  consideration  than  they  seemed  to  merit  two 
thousand  years  ago  the  views  of  my  contemporaries  who  held  that 
extermination  and  survival  have  a  good  deal  to  do  with  fitness, 
but  I  should  still  contend  that  the  study  of  fitness  is  the  true 
aim  of  biology." 

This  comment  on  the  current  interpretation  of  the  essay  on 
"The  Physical  Basis  of  Life"  seems  to  me  to  be  good  common 
sense  and  therefore  good  science ;  and  it  also  seems  to  me  to  be 
a  legitimate  application  of  the  teachings  of  the  "  Parts  of  Animals." 

Huxley  makes  many  references  to  the  problems  of  biology  in 
later  essays,  but  space  will  permit  us  to  examine  none  except  the 
last.  In  1894  I  find  certain  Prolegomena  (IX.  i,  1894)  in  which  it 
is  easy  to  read  between  the  lines  clear  indications  that,  notwith- 
standing the  period  represented  by  the  essay  on  "The  Physical 
Basis  of  Life,"  Huxley  ended  as  he  began, — almost,  if  not  alto- 
gether, in  the  old-fashioned  conviction  that  living  things  do,  in 
some  way  and  in  some  degree,  control  or  condition  inorganic  nature ; 
that  they  hold  their  own  by  setting  the  mechanical  properties  of 
matter  in  opposition  to  each  other,  and  that  this  is  their  most 
notable  and  distinctive  characteristic.  He  says  the  flora  of  the 
region  where  he  writes  was  in  a  "  state  of  nature "  until  three  or 
four  years  before,  when  the  "  state  of  nature  was  brought  to  an 
end,  so  far  as  a  small  patch  of  soil  is   concerned,  by  the  interven- 


HUXLEY,  AND   THE  PROBLEM  OF  THE  NATURALIST      43 

tion  of  man.  The  patch  was  cut  off  from  the  rest  by  a  wall.  .  .  . 
In  short,  it  was  made  into  a  garden.  ...  It  will  be  admitted  that 
the  garden  is  as  much  a  work  of  art  or  artifice  as  anything  that 
can  be  mentioned.  The  energy  localized  in  certain  human  bodies, 
directed  by  similarly  localized  mtellects,  has  produced  a  collocation 
of  other  material  bodies  which  could  not  be  brought  about  in  a 
state  of  nature.  The  same  proposition  is  true  of  all  the  works  of 
man's  hands,  from  a  flint  implement  to  a  cathedral  or  a  chronom- 
eter :  and  it  is  because  it  is  true  that  we  call  these  things  arti- 
ficial, term  them  works  of  art  or  artifice,  by  way  of  distinguishing 
them  from  the  products  of  the  cosmic  process,  working  outside 
man,  which  we  call  nature,  or  works  of  nature.  The  distinction 
thus  drawn  between  the  works  of  nature  and  those  of  man  is 
universally  recognized,  and  it  is,  as  I  conceive,  both  useful  and 
justifiable." 

I  trust  that  the  thoughtful  reader  will  perceive  that  the  legiti- 
mate pursuit  of  this  line  of  reflection  leads  straight  back  to  the 
Aristotelian  statement,  in  the  essay  of  1854  (III.  ii.  40),  that  "to 
the  student  of  life  [as  contrasted  with  the  student  of  physics]  the 
aspect  of  nature  is  reversed.  Here  incessant  and,  so  far  as  we 
know,  spontaneous  change  is  the  rule;  rest  the  exception  —  the 
anomaly  to  be  accounted  for.  Living  things  have  no  inertia  and 
tend  to  no  equilibrium." 

Many  biologists  find  their  greatest  triumph  in  the  doctrine  that 
the  living  body  is  a  "  mere  machine  "  ;  but  a  machine  is  a  colloca- 
tion of  matter  and  energy  working  for  an  end,  not  a  spinning  toy ; 
and  when  the  living  machine  is  compared  to  the  products  of  human 
art,  the  legitimate  deduction  is  that  it  is  not  merely  a  spinning 
eddy  in  a  stream  of  dead  matter  and  mechanical  energy,  but  a 
little  garden  in  the  physical  wilderness ;  that  the  energy  localized 
in  living  bodies,  directed  by  similarly  localized  vitality,  has  pro- 
duced a  collocation  of  other  material  bodies  which  could  not  be 
brought  about  in  a  state  of  physical  nature,  and  that  the  distinc- 
tion thus  drawn  between  the  works  of  non-vital  nature  and  those 
of  life  is  both  useful  and  justifiable. 

What  this  distinction  may  mean  in  ultimate  analysis  I  know 
no  more  than  Aristotle  or  Huxley  ;  nor  do  I  believe  that  any  one 
ever  will  know  until  we  find  out.     One  thing  we  may  be  sure  it 


44  THE  FOUNDATIONS  OF  ZOOLOGY 

does  not  mean  —  that  the  living  world  is  anything  but  natural ;  for 
all  men  of  science  must  agree  with  Aristotle  ("  Parts  of  Animals," 
III.  ii.  i6)  that  "in  all  our  speculations,  therefore,  concerning 
nature,,  what  we  have  to  consider  is  the  general  rule"  (not  forces, 
or  causes,  or  necessary  laws).  "  For  that  is  natural  ivhich  holds 
good  either  universally  or  generally."  If  we  are  to  understand 
this  fitness  which  is  so  distinctive  of  living  things,  this  must  be 
brought  about,  not  by  keeping  it  locked  out  of  sight  as  a  chamber 
of  horrors,  but  by  bringing  it  into  the  bright  light  of  day ;  by 
"intending  the  mind"  upon  it;  by  attacking  it  with  Descartes' 
method  of  using  one's  reason  rightly  for  the  discovery  of  truth. 
Whether  this  method  is  or  is  not  adequate,  we  shall  know  when 
we  find  out ;  but  we  have  no  other,  and  the  discoveries  of  Wallace 
and  Darwin  give  a  basis,  not  for  a  belief,  but  for  a  hope  that  it 
may  some  day  prove  adequate. 

Times  are  changed  since  Huxley  warned  his  hearer  in  1868 
that,  in  accepting  protoplasm  as  the  physical  basis  of  life,  he  was 
"  placing  his  foot  on  the  first  rung  of  a  ladder  which,  in  most 
people's  estimation,  is  the  reverse  of  Jacob's  and  leads  to  the  an- 
tipodes of  heaven."  Nowadays  "  Scientific  Rip  Van  Winkle  "  and 
"  Aristotelian "  arc  the  mildest  phrases  applied  to  him  who  holds 
that  life  is  more  than  a  basis,  —  to  him  who  doubts  whether  the 
essay  states  the  whole  or  even  the  most  essential  part  of  the 
case;  and  he  is  lucky  if  he  is  not  told  that  he  is  a  "Spiritualist," 
"false  to  the  spirit  of  Science";  or  at  the  very  least  that  he  is 
"illogical."  In  this  case  he  can  only  say  with  Huxley  (IX.  10, 
1894)  that  "if  it  is  urged  that  the  .  ,  .  cosmic  process  cannot  be 
in  antagonism  with  that  .  .  .  which  is  part  of  itself,  I  can  only 
reply  that  if  the  conclusion  that  the  two  are  antagonistic  is  logi- 
cally absurd,  I  am  sorry  for  the  logic,  because,  as  we  have  seen, 
the  fact  is  so "  ;  or,  as  Aristotle  expresses  it,  it  holds  good. 

My  own  interest  in  this  distinction  is  entirely  practical  and  not 
philosophical.  Whatever  philosophical  basis  it  may  have  or  may 
not  have,  it  seems  to  me  that  no  one  can  question  its  practical 
bearing  on  the  study  of  biology  at  the  present  day  and  for  many 
ages  to  come.  If  it  is  urged  that  our  knowledge  of  the  external 
world  is  destined  to  be  resolved,  in  the  long  run,  into  our  con- 
sciousness  of   changes   in    the   physical    basis    of    our   minds,    and 


HUXLEY,   AND    THE  PROBLEM  OF  THE  NATURALIST       45 

that  the  "external  world"  to  which  plants  and  animals  respond  is 
also  to  be  resolved  into  changes  in  their  physical  basis,  I  am 
quite  willing  to  admit  this  possibility ;  as  I  am  ready  to  admit 
that,  for  anything  I  know  to  the  contrary,  the  reality  of  both  the 
external  world  and  the  physical  basis  itself  may  consist  in  being 
perceived  or  known,  but  I  hold  it  unwise  to  forget  that  the  same 
daily  experience  which  justifies  our  confidence  in  the  orderly  se- 
quence of  external  nature  also  warrants  the  assumption  that  their 
external  world  is  the  same  as  ours.  The  question  whether  its 
reality  is  ideal  or  material  or  both  has  no  more  to  do  with  this 
purely  practical  confidence  than  has  the  presence  or  absence  in  a 
dog  or  an  oak  tree  of  conscious  belief  in  it. 

They  who  hold  the  faith  that  science  will  some  day  be  able  to 
demonstrate,  in  the  structure  of  the  brain,  the  origin  of  such  actions 
as  writing  a  review  of  Huxley's  Essays,  are  quite  welcome  to  their 
faith  ;  but  I  hold,  as  a  purely  practical  matter,  that  they  may  find 
out  in  a  much  shorter  way  why  I  have  written  this  article  ;  and 
I  also  hold  that  this  is  likely  to  be  the  case  for  some  considerable 
time.  I  also  believe  with  Aristotle  that  the  most  practical  way 
within  our  reach  of  studying  that  adjustment  between  the  organism 
and  the  external  world  —  that  fitness  —  which  constitutes  life,  is  to 
learn  all  we  can  about  the  physical  basis  and  all  we  can  about  its 
fitness  ;  and  I  hold  fast  to  this  purely  practical  confidence  without 
any  faith  in  the  unknown  biology  of  the  distant  future,  and  most 
assuredly  without  any  desire  to  discount  it. 

I  must  ask,  however,  what  reason  there  is  for  thinking  that 
belief  that  my  volition  is  both  real  and  part  of  the  cosmic  process 
is  logically  absurd. 

The  greatest  of  all  my  many  great  debts  to  Huxley  is  the 
clear  perception  that  there  is  no  antagonism  between  belief  that 
all  the  phenomena  of  nature,  including  those  of  life  and  mind,  are 
mechanical,  and  my  confidence  in  the  value  of  my  reason.  If 
Huxley  is  right  in  the  assertion  that  mechanical  principles  are 
nothing  more  than  generalized  statements  of  our  experience,  —  as- 
I  am  convinced  that  he  is,  —  and  if  the  widest  of  all  generaliza- 
tions from  my  experience  is  that  my  volition  counts ;  how  can 
belief  in  the  value  of  my  reason  be  logically  absurd .-'  May  not 
the  logical  absurdity  lie  with   them  who    hold   that   proof  that  my 


46 


THE  FOUNDATIONS  OF  ZOOLOGY 


rational  actions  are  no  more  than  might  have  been  expected  from 
the  working  of  the  mechanism  of  my  body,  would  also  prove 
that  my  reason  is  "as  completely  without  any  power  to  modify 
that  working,  as  the  steam-whistle  which  accompanies  the  work  of 
a  locomotive  engine  is  without  influence  upon  its  machinery "  ? 


LECTURE    III 

NATURE   AND    NURTURE 


LECTURE    III 

NATURE    AND    NURTURE 

This  chapter,  which  all  who  have  attended  my  lectures  during 
the  last  ten  years  will  find  familiar,  does  not  deal  with  the  inter- 
minable question  whether  "acquired  characters"  are  inherited,  but, 
granting  that  this  may  be  the  case,  it  is  an  attempt  to  weigh  the 
value  of  this  "factor"  in  natural  history. 

Herbert  Spencer  tells  us  that  the  segmentation  of  the  backbone 
is  the  inherited  effect  of  fractures,  caused  by  bending,  but  Aristotle 
has  shown  ("Parts  of  Animals,"  I.  i.)that  Empedocles  and  the  ancient 
writers  err  in  teaching  that  the  bendings  to  which  the  backbone 
has  been  subjected  are  the  cause  of  its  joints,  since  the  thing  to 
be  accounted  for  is  not  the  presence  of  joints,  but  the  fitness  of 
the  joints  for  the  needs  of  their  possessor. 

It  is  an  odd  freak  of  history  that  we  of  the  end  of  the  nine- 
teenth century  are  called  upon  to  reconsider  a  dogma  which  was 
not  only  repudiated  two  thousand  years  ago,  but  was  even  then 
called  antiquated.  "  Is  there  anything  whereof  it  may  be  said : 
See !  this  is  new .''  It  hath  been  already  of  the  old  time  which 
was  before  us." 

In  this  day  of  laboratories,  are  we  not  in  danger  of  forgetting 
the  first  principle,  so  clearly  put  by  Aristotle,  that  the  thing  to 
be  explained  is  not  the  structure  of  organisms,  but  the  fitness  of 
this  structure  for  the  needs  of  living  things  in  the  world  in  which 
they  pass  their  lives .''  We  must  be  on  our  guard  lest  the  great 
discovery  that  protoplasm  is  the  physical  basis  of  life  obscure  the 
truth  that  what  Huxley  has  called  the  physical  basis  is  one  thing, 
while  what  Aristotle  has  called  the  essence  of  life  is  quite  another 
thing.  The  physical  basis  of  a  locomotive  engine  is  the  expan- 
sion of  steam,  but  its  essence  is  fitness  for  the  service  of  man. 

E  49 


50  THE  FOUNDATIONS   OF  ZOOLOGY 

Since  we  accept  the  utility  of  steam-engines  as  a  fact  that 
does  not  call  for  explanation,  we  say  we  understand  them  when 
we  have  discovered  that  they  do  neither  less  nor  more  than  their 
mechanical  structure  would  lead  us  to  expect.  It  is  also  clear 
that  we  might  understand  them,  in  this  sense  of  the  word,  even 
if  they  grew,  like  animals,  ready  made ;  although  it  is  equally 
clear  that  we  should  ask,  in  this  case,  how  they  became  fitted  for 
human  needs ;  and  that  we  should  not  admit  that  we  understand 
them  so  long  as  this  question  is  unanswered.  So  it  is,  not  only 
with  the  works  of  man  and  other  living  things,  but  with  the  liv- 
ing things  themselves.  All  they  do  may  sometime  prove  no  more 
than  might  be  expected  from  their  physical  basis;  but  this  proof 
would  not  show  why  the  things  they  do  are  useful  to  the  beings 
that  do  them,  or  to  their  species. 

While  there  is  nothing  novel  in  Herbert  Spencer's  well-known 
dictum,  that  life  is  adjustment,  it  should  help  the  modern  reader 
to  grasp  the  significance  of  Aristotle's  teaching,  to  the  effect  that  the 
essence  of  a  living  being  is  not  protoplasm,  but  purpose.  A  living 
being  is  a  being  with  properties  which  are  useful  to  the  possessor 
or  to  his  species. 

If,  like  Paley,  I  kick  a  stone,  I  may  change  its  position,  raise 
its  temperature,  and  bring  about  other  changes  that  might  all  be 
computed  from  a  few  simple  data.  What  happens  if,  instead  of 
a  stone,  I  kick  a  dog  ? 

In  addition  to  certain  changes  which  are  obviously  mechanical, 
like  those  in  the  stone,  I  start  a  new  set  of  changes  which  could 
never  be  computed  from  the  study  of  the  kick  alone.  But  note 
this  remarkable  fact :  Show  me  the  dog,  and  I  may  be  able  to 
tell  you  what  he  will  do.  If  he  have  short  hair,  a  pink  skin,  a 
big  occipital  crest,  great  cheek  muscles,  a  long  mandibular  bone, 
a  short  nose  with  little  pigment,  small  red  eyes  and  crooked  legs, 
he  will  not  act  like  a  dog  with  silky  ears,  curly  hair,  large  dark 
eyes,  a  long,  black  pointed  nose,  a  bushy  tail,  and  long  legs  with 
big  feet. 

What  has  the  color  of  a  dog's  nose  or  the  size  of  his  feet  to 
do  with  the  effect  of  the  kick .''  Obviously,  nothing  at  all ;  but 
the  changes  in  the  dog  which  follow  the  kick  are  not  its  effect, 
for  they  might  follow  an  unsuccessful  attempt  to  kick  precisely  as 


NATURE  AND  NURTURE  $1 

they  follow  an  actual  blow.  The  color  of  his  eyes  and  the  other 
marks  are  racial  characteristics  which  show  what  his  ancestry 
has  been ;  how  his  parents  and  more  remote  progenitors  have 
behaved  under  similar  assaults.  With  this  scientific  knowledge  of 
dogs  we  may  conjecture,  with  some  confidence,  how  this  one  will 
behave ;  but  in  order  to  compute  his  conduct  with  anything  like 
accuracy,  we  must  have  still  more  information.  If  his  master 
habitually  beat  or  bully  him,  he  will  not  act  like  a  dog  brought 
up  with  more  discretion.  If  he  be  young,  and  have  not  learned  in- 
dependence and  self-reliance  and  distrust  of  strangers,  he  will  not 
act  like  an  older  and  wiser  dog ;  and  if  eyes  and  teeth  and  limbs 
be  failing  from  old  age,  his  conduct  will  be  still  different.  If  the 
kick  wake  him  from  sleep,  he  will  not  act  like  a  dog  disturbed 
while  eating ;  nor  will  a  lost  dog,  oppressed  by  a  sense  of  his 
own  friendlessness,  act  like  one  whose  master  is  near ;  nor  one 
assaulted  at  home  like  one  on  strange  ground,  where  he  has  no 
rights ;  nor  one  attacked  in  the  discharge  of  his  duty  like  one 
detected  in  forbidden  pleasure  or  in  theft.  The  attitude  of  the 
assailant,  or  even  such  little  things  as  the  size  of  the  pupil  of  his 
eye,  or  the  contraction  of  one  or  another  facial  muscle,  will  tell 
the  dog  what  emotions  accompany  the  kick;  and,  if  I  myself  be 
accompanied  by  a  dog,  this  third  party  may  modify  the  result 
without  any  share  in  the  assault. 

What  a  difference  between  a  kick  against  a  dog  and  one 
against  a  stone !  In  one  case  the  simple  conditions  may  be  stated 
in  few  words,  and  the  result  may  be  computed ;  while  in  the 
other,  a  book  would  not  suffice  for  the  statement  of  all  the  facts, 
and  the  best  science  of  our  day  is  powerless  to  compute  the 
result. 

I  am  fully  prepared  to  believe,  whenever  it  is  proved,  that  all 
the  conditions  which  modify  the  result  are  embodied,  in  one  way 
or  another,  in  the  structure  of  the  dog ;  for  I  know  no  reason 
why  we  should  seek  them  anywhere  else.  While  there  will  be 
plenty  of  time  for  a  positive  opinion  when  it  is  proved,  I  see  no 
reason  to  doubt  that,  if  the  dog's  body  could  be  preserved  without 
change,  it  might,  some  day  in  the  ages  to  come,  be  studied  by  a 
naturalist  who  would  be  able  to  tell  what  conduct  would  have 
followed  the  kick,  just  as  we  foresee  the  effect  of  an  opened  valve 


52  THE  FOUNDATIONS  OF  ZOOLOGY 

in  a  steam-engine.  If  absence  of  disproof  were  proof,  they  who 
assert  that,  so  far  as  complexity  is  in  question,  the  difference  be- 
tween the  actions  of  a  stone  and  those  of  a  dog  is  merely  a  differ- 
ence of  degree,  not  of  kind,  may  have  some  ground  for  their 
belief,  inasmuch  as  no  one  can  say  it  may  not  some  day  be 
demonstrated.  I,  for  one,  see  no  other  reason,  than  that  no 
one  knows,  for  doubt  whether  sufficient  knowledge  might  not 
enable  us  to  foresee  or  deduce  the  actions  of  the  dog  from  the 
structure  of  his  body  ;  but  we  have  not  yet  noted  the  most  essen- 
tial characteristic  of  his  actions.  They  are  significant.  They 
have  a  meaning.  They  stand  in  judicious  adjustment  to  the 
canine  world ;  and  their  meaning  can  never,  so  far  as  I  can  see, 
be  learned  by  studying  his  body ;  for  if  the  meaning  which  our 
minds  apprehend  is  embodied  in  any  structure,  it  must  be  in  our 
own,  rather  than  in  that  of  the  dog.  It  may  be  that  all  that 
makes  up  the  dog's  external  world  is  imprinted  in  his  organiza- 
tion, and  that  the  naturalist  of  some  distant  age  may  be  able  to 
there  exhibit  it,  just  as  the  photographer  brings  out  the  picture 
on  his  negative ;  but  even  if  this  were  done,  the  picture  would 
still  remain  only  an  image  of  an  external  world  which,  while  more 
limited,  is  otherwise  practically  the  same  as  our  own.  However 
this  may  be,  the  only  way  to  study  the  meaning  of  the  dog's 
actions,  at  the  present  day,  is  to  seek  it  in  his  environment ;  in 
the  conditions  under  which  he  and  his  ancestors  have  lived ;  nor, 
in  order  to  study  this  meaning,  need  one  know  whether  the  dog 
is  aware  of  it. 

While  there  seems  to  be  good  ground  for  reasonable  confi- 
dence that  the  dog  is  conscious  and  rational,  we  know  nothing 
whatever  concerning  the  presence  or  absence  of  consciousness  in 
most  living  things,  although  we  do  know  that  their  actions  are 
beneficial  to  them  and  such  as  our  reason  approves ;  and  that  this 
is  the  real  difference  between  them  and  a  stone ;  for  while  the 
actions  of  the  stone  may,  for  all  I  know  to  the  contrary,  be  useful 
to  the  stone,  my  reason  does  not  approve  the  statement  that  this 
is  the  case,  for  it  is  a  matter  about  which  I  know  nothing. 

Science  may  some  day  enable  us  to  predict  the  actions  of  the 
dog  from  the  study  of  his  body;  but  I  do  not  see  how  we  are  to 
understand  them  without  studying  the  conditions   under  which  he 


I 


NATURE  AND  NURTURE  53 

and  his  ancestors  have  passed  their  lives.  Whether  he  shut  his  eyes, 
throw  back  his  ears,  and,  straightening  his  tail,  plant  his  teeth  in 
my  leg,  or  crouch  at  my  feet,  with  his  muscles  relaxed,  his  ears 
pendent,  and  his  tail  trailing  on  the  ground,  or,  putting  his  tail 
between  his  legs,  run  away  howling,  the  reason  for  his  conduct  is 
not  the  pain  of  the  blow,  but  the  importance  of  escape  from  the 
further  injury  which  may  follow.  The  means  he  adopts  are  those 
which  have  been  favorable  to  this  result  in  the  past  history  of  dogs. 

The  dog,  no  doubt,  knows,  just  as  we  do,  that,  in  the  ordinary 
course  of  events,  the  attack  is  a  sign  of  a  disposition  to  do  him 
farther  harm  ;  and  he  also  knows  he  may  arrest  or  avert  this  by 
doing  something,  on  his  own  part,  to  meet  it ;  but,  in  case  of  most 
organisms,  we  know  only  the  response  and  not  the  consciousness 
of  it. 

The  kick  is  a  sign  of  something  which  may  follow,  and  the 
actions  which  do  follow  are  not  the  effect  of  the  kick,  for  they  are 
directed  or  adjusted,  either  consciously  or  unconsciously,  to  an  event 
of  which  it  is  only  the  forerunner.  This  is  what  we  mean,  or,  at 
least,  an  essential  part  of  our  meaning,  when  we  say  the  dog  is 
alive,  while  the  stone  is  not.  It  is  possible  that  the  properties 
of  the  stone  may  be  useful  to  the  stone,  but  these  words  are  mean- 
ingless to  us ;  although  we  do  know  that  the  properties  of  the 
dog  are  useful  to  the  dog  or  to  his  species.  The  changes  in  the 
stone  are  the  effect  of  the  blow ;  while  those  in  the  dog  are,  in 
some  way,  the  result  of  the  past  history  of  the  dog  and  of  his  an- 
cestors ;  for,  all  through  this  history,  violent  assaults  have  been  asso- 
ciated with  danger  of  further  violence.  This  difference  is  as  wide 
as  the  difference  between  life  and  its  absence ;  and  the  inde- 
pendence of  biology  as  a  science  is  due  to  its  existence.  It  is  what 
Herbert  Spencer  means  by  the  statement  that  life  is  adjustment, 
and  it  is  what  Aristotle  means  by  teaching  that  the  essence  of  a 
living  being  is  not  what  it  is  made  of  nor  what  it  does,  but  why  it 
does  it. 

A  living  thing  is  a  being  which  responds  to  the  changes  which 
go  on  in  the  world  around  it;  for  life  consists  in  the  maintenance' 
of   adjustment   between   the    changes  which    occur  in  the    external 
order  of    nature  and  those  which  go  on  in  the  living  body.      Life 
is  response  to  the   established    order   of    external   nature;    and,  so 


54  THE  FOUNDATIONS  OF  ZOOLOGY 

far  as  it  is  joined  to  consciousness  and  volition  and  reason,  it  is 
identical  with  the  practical  application  of  scientific  knowledge.  If 
we  were  sure  that  all  living  things  are  conscious  and  endowed 
with  memory  and  volition,  as  they  may  be  for  all  I  know  to  the 
contrary,  we  might  define  life  as  knowledge  in  use ;  for  the  re- 
sponsive actions  of  living  things  are  such  that  our  reason  approves 
them  as  judicious  and  beneficial.  This  truth  has  often  found  ex- 
pression in  the  statement  that  living  things  use  the  properties  of 
the  world  around  them  for  their  own  good  or  the  good  of  their 
species. 

The  same  thought  may  be  expressed  by  the  statement  that 
life  is  the  use  of  the  natural  language  of  signs ;  for  each  stimulus 
to  a  vital  act  is  a  sign  with  a  significance ;  and  the  act  is  itself 
a  response  to  the  significance  of  which,  in  course  of  nature,  the 
stimulus  is  a  sign. 

To  study  life  we  must  consider  three  things :  first,  the  orderly 
sequence  of  external  nature ;  second,  the  living  organism  and  the 
changes  which  take  place  in  it ;  and,  third,  that  continuous  adjust- 
ment between  the  two  sets  of  phenomena  which  constitutes  life. 

The  physical  sciences  deal  with  the  external  world,  and  in  the 
laboratory  we  study  the  structure  and  activities  of  organisms  by 
very  similar  methods ;  but  if  we  stop  here,  neglecting  the  rela- 
tion of  the  living  being  to  its  environment,  our  study  is  not  biology 
or  the  science  of  life.  Now,  whatever  its  equivalent  in  the  struct- 
ure of  organisms  may  be,  the  reality  in  our  own  minds  behind 
such  words  as  use,  fitness,  and  response,  is  not  a  phenomenon, 
which  can,  in  this  century  at  least,  be  weighed  or  measured  or 
made  manifest  to  sense,  but  a  relation,  apprehended  by  our  think- 
ing minds ;  for  beneficial  response  is  one  thing,  and  conscious 
apprehension  of  the  benefit  of  response  quite  another  thing.  Men 
who  know  nothing  of  the  sciences  of  optics  and  acoustics  profit, 
like  philosophers,  by  seeing  and  hearing ;  as  do  also  the  snail  and 
the  jelly-fish,  whether  they  know  they  have  eyes  and  ears  or  not. 

While  biology  presents  endless  opportunities  for  the  profita- 
ble application  of  the  methods  of  research  which  are  employed 
in  physical  science,  it  also  brings  before  us  a  new  problem,  the 
problem  of  fitness,  which  demands  new  methods  of  inquiry,  and 
is  different  from  the  physics  and  chemistry  of  the  living  body. 


NATURE  AND  NURTURE  55 

The  origin  of  those  useful  properties  in  the  employment  of 
which  life  consists  is  one  of  the  most  fascinating  and  instructive 
subjects  in  the  whole  range  of  human  inquiry,  for  to  it  knowledge 
itself  ov/es  its  significance. 

While  there  is  so  much  that  we  do  not  know,  we  do  know 
that  the  qualities  which  fit  the  dog  for  his  place  in  nature,  and 
enable  him  to  respond  to  the  changes  which  go  on  in  the  world 
around  him,  are,  in  part,  transmitted  from  his  ancestors,  while  they 
are,  in  part,  the  result  of  his  individual  training  and  experience 
and  education  and  contact  with  the  world. 

The  opinion  that  the  effects  of  his  individual  history  may  be 
transmitted  to  his  descendants,  the  belief  that  he  may  inherit  the 
effects  of  the  experience  and  education  and  training  of  his  an- 
cestors, has  come  to  be  formulated  as  "  the  inheritance  of  ac- 
quired characters";  although  I,  for  my  own  part,  never  use  this 
form  of  words  without  protest.  If  any  assert  that  the  dog  in- 
herits anything  which  his  ancestors  did  not  acquire,  their  words 
seem  meaningless ;  for,  as  we  use  words,  everything  which  has 
not  existed  from  the  beginning  must  have  been  acquired  ;  although 
one  may  admit  this  without  admitting  that  the  nature  of  a  dog 
is,  wholly  or  to  any  practical  degree,  the  inherited  effect  of  the. 
environment  of  his  ancestors. 

Francis  Galton,  borrowing,  I  suppose,  from  "The  Tempest," 
many  years  ago  contrasted  the  nature  and  the  nurture  of  living 
things ;  and  I  propose  to  examine  the  question  whether  the  nature 
of   a  dog  or  of  any  other  living  being  is  inherited  nurture. 

This  is  very  different  from  the  question  whether  the  effects  of 
nurture  are  ever  inherited,  and  I  have  no  desire  or  intention  to 
discuss  this  interminable  subject;  for  I  find  as  little  value  in  the 
a  priori  arguments  of  those  who  hold  that  "  acquired  characters " 
cannot  be  inherited  as  I  find  in  Haeckel's  assertion  that  "belief 
in  the  inheritance  of  acquired  characters  is  a  necessary  axiom  of 
the  Monistic  creed." 

So  far  as  the  question  is  whether  the  nature  of  organisms  is 
wholly  or  to  any  practical  degree  inherited  nurture,  I  think  it  no 
more  than  right  to  say  that  my  own  view  of  the  matter  was 
formed  many  years  ago,  before  the  recent  revival  of  discussion, 
and  that,  while  I  have  followed  this,  I   have   found  no  reason  for 


56  THE  FOUNDATIONS   OF  ZOOLOGY 

making  any  essential  change.  One  morning,  some  time  ago,  I 
•found  in  my  mail  two  papers  by  naturalists  whose  well-earned 
reputation  in  their  own  fields  would  seem  to  entitle  them  to 
speak  with  authority.  In  one  I  read  that  American  indifference 
to  the  destruction  of  our  valuable  timber  is  the  inherited  effect 
of  the  long  war  with  the  primeval  forest  which  our  ancestors 
were  forced  to  carry  on  in  order  to  make  a  home  in  the  new 
world.  The  author  of  the  second  paper  accounts  for  the  great  size 
of  the  eyes  of  certain  deep-sea  fishes  by  attributing  their  enlarge- 
ment to  the  efforts  of  many  generations  to  see  in   "  total "  darkness. 

Conrad  Gesner  tells  us,  in  his  "  Book  of  Animals,"  that  no  book 
is  so  bad  the  thoughtful  reader  may  not  learn  something  from 
it ;  and  if  these  speculations  can  be  made  to  point  a  moral,  they 
are  not  quite  in  vain,  as  they  may  help  us  to  fix  attention  on 
certain  first  principles  which  seem  so  obvious  that  one  would 
think  all  must  admit  them. 

Familiar  experience  teaches  that  living  things  are  often  greatly 
modified  by  the  conditions  to  which  they  are  exposed  during 
their  individual  life,  and  that  the  modifications  which  are  thus 
produced  are  often  useful ;  for  if  this  were  not  the  case,  no  bene- 
ficial effect  could  come  from  training  or  education.  We  all  know 
that  the  congenital  or  natural  powers  and  faculties  of  children  and 
of  those  who  grow  up  in  ignorance  are  very  limited,  and  that  it 
is  practice  which  makes  perfect.  That  judicious  use  often  devel- 
ops and  strengthens  the  parts  which  are  used  is  unquestionable 
and  the  efficiency  of  neglected  organs  often  becomes  impaired.  We 
are  born  with  a  nature  that  makes  the  normal  use  of  our  powers 
a  pleasure,  and  while  aceticism  may  despise  mere  bodily  delights, 
more  generous  wisdom  sees,  in  the  keen  enjoyment  of  normal  or- 
ganic life,  and  in  the  discomfort  or  pain  which  attends  repression, 
especially  in  the  young,  some  of  those  wonderful  adjustments 
which  are  the  very  essence  of  natural  science. 

While  hard  work  is  exhausting,  and  while  the  organic  machine 
is  easily  damaged  by  abuse,  and  is,  at  last,  worn  out  by  use,  normal 
use  is  a  condition  of  its  perfect  development,  and  the  amount  of 
normal  work  it  may  do  without  deterioration  is  astonishing.  In 
the  highly  civilized  and  self-indulgent,  it  is  much  less  likely  to 
wear   out   than    to    rust   out;    and    nothing    could    be    more    short- 


NATURE  AND  NURTURE  57 

sighted  than  impatience  with  the  restlessness  of  children,  although 
no  effeminacy  can  wholly  repress  the  joyous  exuberancy  of  child- 
hood ;  nor  can  any  thoughtful  person  fail  to  see  that  the  impulse 
which  leads  young  animals  to  train  and  develop  their  bodies  by 
sports  and  gambols  is  adaptive. 

All  this,  and  more,  is  implied  by  the  admission  that  there  is 
such  a  thing  as  nurture;  and  one  of  the  first  questions  to  present 
itself,  when  we  consider  the  matter,  is  why  living  things  are  not 
like  the  imaginary  Caliban ;  how  they  come  by  a  nature  on  which 
nurture  will  stick ;  for  it  is  plain  that,  far  from  being  an  explana- 
tion of  nature,  nurture  is  a  fact  which  itself  calls  for  explanation. 

The  most  stable  organs  may  be  modified  by  novel  or  excep- 
tional use,  and  the  most  profound  structural  changes  may  be 
brought  about  by  nurture.  After  Hunter  had  fed  a  sea-gull  on 
grain  for  a  year,  he  found  that  the  inner  coat  of  its  stomach  had 
grown  hard,  and  its  muscles  had  thickened,  thus  forming  a  true 
gizzard,  although  the  sea-gull  normally  has  a  soft  stomach,  as  it 
lives  upon  the  soft  flesh  of  fishes.  It  is  well  known  that  living 
things  are  often  changed  by  mechanical  influences.  The  skull 
of  a  hornless  ram  has  been  found  to  weigh  only  one-fourth  as 
much  as  the  skull  of  a  ram  with  horns ;  and  the  whole  configu- 
ration of  the  skull  of  lop-eared  rabbits  is  altered  by  the  mechanical 
pressure  of  the  drooping  ears.  Hemp  seed  causes  bulfinches  and 
some  other  birds  to  become  black ;  and  we  know,  from  the  obser- 
vations of  many  naturalists,  that  change  of  food  sometimes  changes 
the  colors  of  caterpillars,  or  even  those  of  the  moths  which  they 
produce.  Many  curious  cases  of  this  sort  have  been  recorded,  in 
birds  and  insects,  and  it  seems  reasonable  to  believe  that,  if  un- 
natural food  may  change  the  normal  colors  of  a  species,  the  normal 
colors  may  themselves,  in  some  cases,  be  due  to  the  direct  action 
of  the  natural  food. 

Sometimes  the  effect  of  the  conditions  of  life  is  injurious,  some- 
times neutral,  but  often  it  is  useful  to  a  notable  degree ;  and  it  is 
this  usefulness  —  the  power  to  respond  to  changed  conditions  by 
adaptive  modification — which  is  most  worthy  of  consideration. 
Cold  weather  promotes  the  growth  of  hair  on  mammals,  and  thus 
protects  them  from  the  cold.  The  muscle  which  is  used  grows 
stronger,  and  the  hand  becomes  skilful  by  training. 


58  THE  FOUNDATIONS   OF  ZOOLOGY 

Look  at  a  young  pine  tree  and  examine  its  mode  of  growth. 
No  one  can  doubt  that  the  long,  straight,  tapering  trunk,  and  the 
successive  circles  of  branches,  uniformly  decreasing  in  length  from 
the  spreading  base  to  the  pointed  crown,  serve  a  useful  end ;  that 
the  arrangement  offers  great  resistance  to  storms,  exposes  a  great 
area  of  foliage  to  sun  and  air,  and  has  other  advantages.  Now 
examine  the  arrangement  of  the  buds.  At  the  tip  of  the  central 
axis  is  a  terminal  bud,  pushing  straight  upwards  and  building  the 
crown  of  the  tree,  and  giving  off  lateral  buds  which  build  the 
branches,  and,  becoming  their  terminal  buds,  leave  behind  them 
their  own  series  of  lateral  buds  to  repeat  the  same  process.  The 
shape  of  the  tree,  so  characteristic  that  it  may  be  identified  miles 
away,  is  the  result  of  this  simple  law  of  growth;  and  this  itself  is, 
in  a  certain  sense,  a  result  of  the  mechanical  conditions  of  life. 
Ihe  bud  at  the  top  of  the  crown  is  the  only  one  which  is  sym- 
metrically placed  with  reference  to  the  sources  of  light  and  air  and 
food,  and  its  symmetry  is  the  result ;  while  the  unequal  distribu- 
tion of  these  conditions  of  growth  results  in  the  one-sided  develop- 
ment of  the  other  buds.  If  the  crown  of  the  young  pine  tree  be 
destroyed  by  lightning  or  storm,  or  by  an  enemy,  a  bud  that  would 
otherwise  have  played  a  subordinate  part,  may  fall  heir  to  its 
advantages  and  build  up  a  new  crown.  If  the  tree  be  prostrated 
by  an  accident,  a  new  trunk,  with  its  tapering  crown,  may  spring, 
in  time,  from  a  bud  far  down  the  trunk. 

From  one  point  of  view  the  shape  of  the  pine  tree  seems  to  be 
the  effect  of  the  mechanical  conditions  under  which  it  grows,  for 
unnatural  or  exceptional  changes  in  these  conditions  may  be 
followed  by  abnormal  deviations  from  the  type ;  but  from  another 
point  of  view  the  type  of  the  pine  tree  is  fixed  by  the  constitution 
or  inherent  tendency  of  the  tree  itself,  and  is  independent  of 
external  conditions  ;  for  when  a  pine,  a  spruce,  and  a  larch  grow 
side  by  side  under  the  same  conditions,  each  conforms  to  its  own 
type.  The  so-called  conditions  of  individual  life  are  stimuli,  without 
which  normal  growth  does  not  take  place,  but  they  are  not  deter- 
mining factors,  for  the  change  that  follows  is  due  to  something 
prior  to  and  independent  of  the  stimulus. 

While  it  is  a  matter  of  familiar  experience,  in  every  moment  of 
our  lives,  that  the  stimulus  under  which  a  vital  action  takes  place 


NATURE  AND  NURTURE  59 

is  one  thing,  while  the  character  of  the  action  itself  is  quite  another 
thing,  this  fact  tends  from  its  very  familiarity,  to  slip  out  of  the 
minds  of  students ;  and  two  views  of  the  nature  of  the  process  of 
development  of  the  living  thing  out  of  the  germ,  which  have  been 
argued  for  centuries,  illustrate  this  tendency.  One  school  of  embry- 
ologists  has  long  held  that  the  Qgg  or  germ  produces  the  living  thing 
in  virtue  of  its  inherent  potency,  or  specific  constitution,  which  is, 
in  some  way,  an  embodiment  of  all  that  is  to  be  unfolded  out  of  it ; 
while  the  other  school  finds,  in  the  stimulus  which  is  given  by 
nurture,  in  the  influence  of  the  external  world,  and  in  that  which  the 
parts  of  the  segmenting  o.^^  and  those  of  the  growing  organism 
exert  on  each  other,  the  explanation  of  each  successive  step  in  the 
process  of  development. 

Advocates  of  these  two  views  have  regarded  themselves  as 
opponents,  but  except  that  latent  potency  is  hard  to  lay  hold  of, 
while  mechanical  conditions  readily  lend  themselves  to  experiment, 
I  cannot  see  why  there  should  be  any  real  antagonism;  for  the  evi- 
dence that  each  may  be  true  seems  ample.  Every  change  that 
takes  place  in  the  living  being,  from  the  beginning  to  the  end  of 
individual  life,  may  be  called  forth  by  some  mechanical  stimulus, 
either  within  the  body  or  without ;  and  yet  the  outcome  of  the  whole 
process  may  be  no  more  than  exhaustive  knowledge  of  the  nature  of 
the  germ  would  lead  one  to  expect. 

The  gun  does  not  go  off  until  the  cap  is  exploded,  but  it  hits  the 
mark  because  it  is  aimed.  While  the  distinction  between  the  stim- 
ulus to  a  vital  change  and  the  nature  of  the  change  itself  is  obvious 
enough  in  simple  cases,  we  may  easily  become  confused  and  lose 
sight  of  it  in  handling  complicated  problems. 

A  hen's  &gg  will  not  develop  without  heat  and  fresh  air,  and 
when  these  are  properly  supplied  it  becomes  a  chick,  although 
belief  that  the  heat  causes  the  chick  is  too  grotesque  for  the  sane 
mind ;  for  the  production  of  a  duckling  from  a  duck's  egg  in  the 
same  nest  proves,  if  any  proof  be  needed,  that  while  the  egg  will 
not  develop  without  incubation,  the  outcome  of  the  process  of 
incubation  is  the  result  of  the  inherent  capacity  of  the  Q.^g  itself. 

The  most  notable  peculiarity  of  this  inherent  tendency  or 
specific  constitution  of  living  things  is  its  fitness.  The  ^^^  not  only 
gives  rise  to  a  specific  organism,  but  to  one  that  is  beautifully  and 


6o  THE  FOUNDATIONS  OF  ZOOLOGY 

wonderfully  fitted  for  the  normal  life  of  its  species.  What  interests 
us  is  not  that  the  hen's  egg  becomes  a  chick  while  the  duck's  Q.^g 
becomes  a  duckling  ;  but  that  one  grows  into  exquisite  adjustment 
to  the  life  of  fowls,  while  the  other  becomes  as  admirably  fitted  for 
the  life  of  ducks. 

In  truth,  the  assertion  that  the  future  chick  is  latent  in  the  Q.gg 
seems  to  be  no  more  than  a  generalized  statement  of  observed 
facts,  and  of  our  confidence  that  they  may  be  repeated ;  although  it 
by  no  means  follows  that  the  words,  inherent  potency,  are  useless ; 
for  they  serve  a  useful  purpose  if  they  fix  attention  on  the  fact  that, 
while  that  which  was  an  ^^^  may  under  certain  conditions  become  a 
chick  adapted  for  the  life  of  fowls,  knowledge  of  these  conditions 
fails  to  show  us  why  it  should. 

Here  the  stimulus  comes  from  the  external  world,  but  the  case 
is  just  the  same  when  it  is  internal.  The  well-known  results  of 
castration  prove  that  the  normal  development  of  many  male  mam- 
mals and  birds  depends  upon  some  constitutional  stimulus  which 
comes  from  the  reproductive  organs  to  the  parts  of  the  growing 
body ;  but  who  can  believe  this  an  adequate  explanation  of  the 
short,  sharp  horns,  the  thick  neck,  and  the  ferocity  of  the  bull,  or  of 
the  bright  colors,  the  sharp  spurs,  and  the  high  courage  of  the  cock  ? 

Have  we  any  reason  for  a  different  opinion  when  the  result 
varies  with  the  stimulus }  Under  one  internal  stimulus  a  bud 
becomes  a  jelly-fish,  while,  under  others,  it  may  become  a  hydranth 
or  a  machopolyp  or  a  blastostyle,  but  the  real  problem,  in  this 
case  as  in  the  others,  is  the  production  of  a  beautifully  coordinated 
organism,  with  the  distinctive  characteristics  of  its  species,  and 
with  exquisite  fitness  for  a  life  like  that  of  its  ancestors. 

I  showed,  some  years  ago,  that  a  small  crustacean,  Alpkeus 
heterochelis,  develops  according  to  one  plan  at  Beaufort  in  North 
Carolina,  according  to  a  second  at  Key  West  in  Florida,  while 
it  has  still  a  third  life  history  at  Nassau  in  the  Bahama  Islands ; 
but  no  one  can  believe  that  the  influences  which  cause  this  diver- 
sity in  the  metamorphosis  of  Alpheus  have  anything  to  do  with 
the  final  outcome,  which  is  the  same  in  all  three  places.  The 
case  is  exactly  the  same  when  a  cell  which  would  normally  give 
rise  to  a  half  or  a  quarter  of  the  body  gives  rise  to  the  whole 
under  a  different  stimulus. 


NATURE  AND  NURTURE  6 1 

All  the  machinery  in  a  great  industrial  exposition  may  be 
started  by  a  single  electrical  contact,  but,  however  much  the  dis- 
covery of  the  button  may  interest  us,  it  helps  us  but  little  to 
understand  the  result.  So  it  is  with  living  organisms.  External 
conditions  press  the  button,  but  it  takes  all  the  inherent  potency 
of  living  matter  to  do  the  rest. 

It  is  an  error  to  suppose  great  knowledge  is  needful  for  a 
clear  grasp  of  first  principles.  "  The  largest  views  are  not  always 
the  clearest,  for  he  who  is  short-sighted  will  be  obliged  to  draw 
the  object  nearer,  and  may,  perhaps,  by  a  closer  and  nearer  sur- 
vey, discover  that  which  had  escaped  far  better  eyes." 

The  riches  of  a  great  store  of  information  "  cannot  be  spared 
or  left  behind,  but  it  hindereth  the  march ;  yea,  and  the  care  of 
it  sometimes  loseth  or  disturbeth  the  victory." 

Students  who  are  drifting  on  the  sea  of  facts,  with  which  the 
modern  laboratory  has  flooded  us,  sometimes  declare  that  the 
doctrine  of  adaptation  is  antiquated  and  unscientific  and  perni- 
cious. They  tell  us  that  organisms  have  many  properties  which 
are  not  adaptive,  and  that  we  are  often  unable  to  tell  whether  a 
property  is  adaptive  or  not.  Of  course  this  is  true.  No  one 
supposes  that  susceptibility  to  poisons,  for  example,  is  adaptive  as 
such,  and  our  knowledge  of  nature  is  incomplete  beyond  measure. 

They  tell  us,  too,  that  many  attempts  to  explain  the  uses  of 
parts  are  fanciful  and  worthless.  Unfortunately  this  is  true  also, 
but  the  logic  which  makes  it  a  reason  for  denying  the  reality 
of  fitness  is  enough  to  raise  Paley  from  his  grave. 

While  protoplasm  is,  no  doubt,  the  physical  basis  of  life,  the 
intellectual  basis  of  biology  is  adjustment.  I  should  like  to  see 
hung  on  the  walls  of  every  laboratory  Herbert  Spencer's  defini- 
tion, to  the  effect  that  life  is  not  protoplasm,  but  adjustment;  or 
the  older  teaching  of  the  father  of  zoology,  that  the  essence  of 
a  living  thing  is  not  what  it  is  made  of  nor  what  it  does,  but  why 
it  does  it. 

It  may  seem  to  some  that,  since  capacity  for  nurture  is  part 
of  the  nature  of  living  things,  the  difference  between  nature  and 
nurture  is,  after  all,  apparent  rather  than  real.  Since  what  is 
transmitted  from  parent  to  child  is  not  actual  or  manifest  nature, 
but    only   its   latent    potency,    or,    in    other   words,    a    capacity    for 


62  THE  FOUNDATION'S  OF  ZOOLOGY 

nurture,  the  question  whether  nature  is  inherited  nurture  or  not 
may  seem  a  matter  of  words  and  definitions,  rather  than  a  real 
problem  of  things ;  although  no  one  can  lose  sight  of  the  truth 
that  aptitude  for  nurture  is  not,  unfortunately,  the  same  as  apti- 
tude for  beneficial  nurture.  It  is,  at  most,  no  harder  to  acquire 
pernicious  habits  than  to  acquire  good  ones ;  no  harder  to  culti- 
vate bodily  infirmity,  or  logical  inconsequence,  or  mental  imbe- 
cility, or  moral  obliquity,  than  to  develop  and  make  the  best  of 
our  faculties  and  opportunities.  He  who  has  passed  the  plastic 
age  without  adding  to  his  nature  much  nurture  he  would  gladly 
be  quit  of,  is  either  more  fortunate  or  less  particular  than  the  bulk 
of  mankind.  While  it  may  be  true  that  we  acquire  no  nurture 
but  that  which  our  nature  permits,  it  is  no  less  true  that  this 
nature  permits  a  wide  range  of  good  and  bad ;  and  that  it  by 
no  means  binds  us  to  make  of  our  nature  all  that  it  permits.  All 
this  seems  true  of  other  living  things  as  well,  and  the  view  that 
nature  is  inherited  nurture  throws  no  light  on  the  problem  of 
fitness. 

Belief  that  something  is  added  to  our  nature  by  experience, 
and  training,  and  education,  rests  on  deliberate  or  unconscious 
acceptance  of  some  such  definition  of  nature  as  that  which  Alci- 
phron  gives ;  and,  as  the  modern  zoologist,  who  regards  nature  as 
the  inherited  effect  of  past  nurture,  seems  to  lose  sight  of  Euphra- 
nor's  analysis  of  this  definition,  I  beg  leave  to  refresh  his  memory 
by  a  short  quotation  from  the  old  dialogue. 

Euphra7ior.  You  seem  very  much  taken  with  the  beauty  of  nature. 
Be  pleased  to  tell  me,  Alciphron,  what  those  things  are  which  you  esteem 
natural,  or  by  what  mark  I  may  know  them. 

Alciphron.  For  a  thing  to  be  natural,  for  instance,  to  the  mind  of  man, 
it  must  appear  originally  therein  :  it  must  be  universal  in  all  men  :  it  must 
be  invariably  the  same  in  all  nations  and  ages.  These  limitations  of  origi- 
nal, universal,  and  invariable  exclude  all  those  notions  of  the  human  mind 
which  are  the  effect  of  custom  and  education.  The  case  is  the  same  with 
respect  to  all  other  species  of  beings.  A  cat,  for  example,  hath  a  natural 
inclination  to  pursue  a  mouse,  because  it  agrees  with  the  forementioned 
marks.  But  if  a  cat  be  taught  to  play  tricks,  you  will  not  say  these  tricks 
are  natural.  For  the  same  reason,  if  upon  a  plum  tree  peaches  and  apricots 
are  engrafted,  nobody  will  say  they  are  the  natural  growth  of  the  plum  tree. 

Euph.    But  to  return  to   man :    it  seems  you  allow  those  things  alone 


NATURE  AND  NURTURE  63 

to  be  natural  to  him  which  show  themselves  upon  his  first  entrance  into 
the  world ;  to  wit,  the  senses,  and  such  passions  and  appetites  as  are  dis- 
covered upon  the  first  application  of  their  respective  objects. 

Ale.    That  is  my  opinion. 

Euph.  Tell  me,  Alciphron,  if  from  a  young  apple  tree,  after  a  certain 
period  of  time,  there  should  shoot  forth  leaves,  blossoms,  and  apples,  would 
you  deny  these  things  to  be  natural,  because  they  did  not  discover  and 
display  themselves  in  the  tender  bud? 

Ak.    I  would  not. 

Euph.  And  suppose  that  in  a  man,  after  a  certain  season,  the  appe- 
tite of  lust,  or  the  faculty  of  reason,  shall  shoot  forth,  open,  and  display 
themselves,  as  leaves  and  blossoms  do  in  a  tree ;  would  you,  therefore, 
deny  them  to  be  natural  to  him,  because  they  did  not  appear  in  his  original 
infancy  ? 

Ale.    I  acknowledge  I  would  not. 

Eiiph.  It  seems,  therefore,  that  the  first  mark  of  a  thing's  being  natural 
to  the  mind  was  not  warily  laid  down  by  you ;  to  wit,  that  it  should  ap- 
pear originally  in  it. 

Ale.    It  seems  so. 

Euph.  Again,  inform  me,  Alciphron,  whether  you  do  not  think  it  natural 
for  an  orange-plant  tree  to  produce  oranges? 

Ale.    I  do. 

Euph.  But  plant  it  in  the  north  end  of  Great  Britain,  and  it  shall 
with  great  care  produce,  perhaps,  a  good  salad ;  in  the  southern  parts  of 
the  same  island,  it  may,  with  much  pains  and  culture,  thrive  and  produce 
indifferent  fruit ;  but  in  Portugal  or  Naples  it  will  produce  much  better 
fruit  with  little  or  no  pains.     Is  this  true  or  not? 

Ale.    It  is  true. 

Euph.  The  plant  being  the  same  in  all  places,  doth  not  produce  the 
same  fruit  —  sun,  soil,  and  cultivation  making  a  difference. 

Ale.    I  grant  it. 

Euph.  And  since  the  case  is,  you  say,  the  same  with  respect  to  all 
species,  why  may  we  not  conclude,  by  a  parity  of  a  reason,  that  things  may 
be  natural  to  humankind,  and  yet  neither  found  in  all  men,  nor  invariably  the 
same  when  they  are  found  ?  And,  as  those  fruits  which  grow  from  the  most 
generous  and  mature  stock,  in  the  choicest  soil,  and  with  the  best  culture,  are 
most  esteemed  ;  even  so  ought  we  not  to  think  those  sublime  truths,  which  are 
the  fruits  of  mature  thought,  and  have  been  rationally  deduced  by  men  of  the 
best  and  most  improved  understandings,  to  be  the  choicest  productions  of 
the  rational  nature  of  man?  And,  if  so,  being  in  fact  reasonable,  natural,  and 
true,  they  ought  not  to  be  esteemed  unnatural  whims,  errors  of  education,  and 
groundless  prejudices,  because  they  are  raised  and  forwarded  by  manuring 
and  cultivating  our  tender  minds,  because  they  take  early  root,  and  sprout  forth 
betimes  by  the  care  and  diligence  of  our  instructors. 


64  THE  FOUNDATIONS   OF  ZOOLOGY 

The  belief  that  nature  is  inherited  nurture  so  obviously  fails  to 
throw  light  on  the  problem  of  fitness  that  most  of  the  modern  advo- 
cates of  this  opinion  claim  no  more  than  that  nurture  supplies  the 
raw  material  from  which  natural  selection  picks  out  and  preserves 
the  good,  the  useful,  the  fit;  while  the  bad,  the  injurious,  the  unfit, 
is  neglected;  but  I  hope  my  readers  may  find  reason  to  ask  whether 
we  can  be  sure  that  nurture  has  even  this  amount  of  influence. 

Living  things  are  preeminently  distinguished  by  what  is  best 
expressed  by  the  word  fitness;  they  are  adjusted  to  the  world 
around  them  in  such  a  way  as  to  force  us  to  believe  that  the  use 
to  which  their  organization  is  put  has,  in  some  way,  been  the  con- 
trolling factor  in  the  production  of  the  organization  itself.  There 
is  no  escape  from  the  belief  that  the  adjustment  of  the  eye  to  the 
principles  of  optics,  its  fitness  for  vision,  has,  in  some  way,  guided 
and  controlled  its  history;  that  it  has  come  into  existence  for  seeing, 
or  by  seeing,  or  because  it  sees.  Darwin  and  Wallace  have  shown 
how  the  use  of  a  part  determines  its  structure  through  the  extermi- 
nation of  the  relatively  unfit,  and  the  survival  of  the  relatively  fit; 
and  I  shall, try,  in  another  place,  to  show  that  this  explanation  is 
adequate  and  satisfactory;  but  at  present  we  are  concerned  only 
with  the  opinion  that  the  eye  has  been  made,  wholly  or  in  part, 
by  seeing. 

Since  the  conditions  of  life  often  tend,  as  we  have  seen,  to 
modify  organisms  in  such  a  way  as  to  fit  them  for  these  very  con- 
ditions; since,  for  example,  the  trained  eye  sees  more  than  the 
untrained  eye ;  since,  within  certain  limits,  extra  demands  upon  a 
muscle  make  it  more  able  to  do  the  extra  work,  —  may  not  the  spe- 
cific constitution  of  each  organism  have  been  produced  in  somewhat 
the  same  way.-*  May  it  not  be  the  inherited  result  of  the  influence 
of  the  conditions  under  which  its  ancestors  lived;  preserved,  it  may 
be,  by  natural  selection.''  Since  the  pine  tree  does  not  grow  up 
without  the  mechanical  influence  of  its  environment,  may  not  the 
inherited  tendency  to  which  its  shape  is  due  have  been  caused 
by  the  direct  mechanical  action  of  the  environment  of  past 
generations .'' 

This  is  a  fair  question,  and  if  it  were  asked  by  a  boy,  or  by  one 
unfamiliar  with  the  subject,  I  should  welcome  it  as  a  sign  of  intelli- 
gent interest;   but  when  it  is  asked  by  a  naturalist,  I  can  look  at  it 


NATURE  AND  NURTURE  65 

only  as  an  indication  of  culpable  ignorance  of  history;  for  the 
hypothesis  has  been  tried  and  found  wanting,  and  it  was  rejected 
as  inadequate  more  than  two  thousand  years  ago.  To  come  down 
to  modern  times,  Wallace,  Darwin,  Huxley,  and  Gray,  men  who 
were,  assuredly,  unprejudiced  by  opposition  to  the  doctrine  of  the 
mutability  of  species,  have  all  told  us  that  they  studied  Lamarck 
with  all  diligence,  and  found,  in  his  works  on  this  subject,  nothing 
of  value. 

The  views  of  the  Neo-Lamarckians,  as  I  understand  them,  are 
somewhat  broader  than  those  of  Lamarck,  but  fundamentally  the 
same,  and,  briefly  stated,  are  as  follows:  The  useful  changes 
which  are  produced  in  the  structure,  habits,  instincts,  and  other 
faculties  of  living  things,  through  contact  with  the  world  around 
them,  are  inherited  by  their  children;  and  this  inheritance,  aided, 
it  may  be,  by  natural  selection,  is  an  efficient  factor  in  the  origin  of 
species,  and  has  gradually  adjusted,  or  given  material  aid  in  adjust- 
ing, the  characteristics  of  each  organism  to  its  needs.  Stated  still 
more  briefly,  it  is  the  doctrine  that  organic  evolution  has  been 
brought  about,  or  at  least  greatly  aided,  by  the  inheritance  of 
nurture. 

We  must  now  dwell  upon  a  point  which  seems  worthy  of  atten- 
tion. Lamarck  believed  that  the  useful  effects  of  the  conditions  of 
life  are  the  ones  which  are  inherited,  and  this  is  the  only  point 
worth  notice;  for  if  these  effects  may  be  indifferently  useful,  use- 
less, or  injurious,  they  can  have  no  bearing  upon  the  origin  of 
adjustment.  In  inorganic  nature  it  may  be  an  even  chance  whether 
an  external  change  be  destructive  or  preservative,  but,  when  we 
remember  how  narrow  the  range  of  adjustment  of  each  living  being 
is,  the  probability  that  haphazard  effects  will  be  injurious  or  neutral 
rather  than  beneficial  is  prodigious.  Even  if  they  are  inherited,  the 
effects  of  nurture  cannot  cumulate  in  adaptation  except  as  an  acci- 
dent so  improbable  that  only  the  most  conclusive  evidence  can 
prove  such  an  event;  unless  indeed  it  can  be  shown  that  nurture 
is  beneficial  independently  of  selection. 

While  the  chances  seem  all  against  adaptive  modification 
by  the  direct  action  of  the  conditions  of  life,  I  think  we  may 
challenge  the  Lamarckian  to  show  a  single  species  which  has 
been  modified  to  its  own  disadvantage.       There    are    species  which 


66  THE  FOUNDATIONS  OF  ZOOLOGY 

have  been  thrown  out  of  harmony  with  their  environment  by  some 
external  change  to  which  they  failed  to  respond,  and  individuals 
are  often  put  at  the  greatest  disadvantage,  or  even  destroyed,  for 
the  good  of  the  species  as  a  whole,  but  there  is  not  a  single 
example  of  the  disadvantageous  modification  of  a  species  in  a 
state  of  nature ;  although  man  is  able  to  produce,  for  his  own 
purposes,  such  monsters  as  double  flowers,  oranges  and  grapes 
without  seeds,  and  laying  hens  which  never  sit,  and  thus  to 
demonstrate  that  species  present  no  inherent  obstacle  to  injurious 
modification. 

The  Lamarckians  have  brought  together  a  long  list  of  examples 
of  the  useful  modification  of  individuals  by  external  influences, 
but  no  one  has  tabulated  the  neutral  or  hurtful  modifications. 
Still  we  find  reason  to  believe  that  organisms  do  tend  to  respond, 
in  a  favorable  way,  to  certain  external  changes,  and  we  may  fairly 
call  upon  the  Lamarckian  to  explain  how  this  useful  property  was 
acquired.  How,  for  example,  did  our  muscles  acquire  the  ten- 
dency to  become  strengthened  by  exercise .-' 

Certain  zealous  Lamarckians  tell  us,  as  if  it  were  a  sufficient 
explanation,  that  the  benefit  which  comes  with  the  normal  use  of 
our  muscles  is  due  to  the  properties  of  living  matter ;  although  I 
am  not  aware  that  any  modern  naturalist  attributes  it  to  anything 
else.  I  shall  try  to  show,  Lectures  VI IL  and  IX.,  that  the  only 
path  in  which  we  can  have  any  well-grounded  hope  for  progress  in 
the  explanation  of  adaptive  types  takes  its  departure  from  that  con- 
ception of  nature  which  leads  us  to  seek  for  the  origin  of  the 
properties  which  exhibit  adaptation  in  the  physical  basis  of  living 
beings.  If  any  interpret  the  opinion  that  the  origin  of  these 
properties  must  there  be  sought  as  an  assertion  that  it  has  there 
been  found,  I  do  not  see  that  their  impetuosity  has  any  bearing  on 
the  point  at  issue,  which  here,  as  in  other  cases,  is  the  question 
how  the  living  being  comes  to  exhibit  these  properties  under 
normal  stimuli  in  such  a  way  as  to  be  adaptive.  The  increased 
power  to  use  our  muscles,  which  comes  with  practice,  is,  no  doubt, 
due,  in  the  main,  to  improvement  in  the  nervous  system,  although 
normal  use  is  essential  to  the  healthful  development  of  the  muscle 
itself,  for  its  nutrition  is  promoted  by  normal  exercise,  and  this 
result  may  be  imitated  by  massage  or  by  electrical  stimulation. 


NATURE  AND  NURTURE  6y 

It  has  seemed  to  some  that  the  pathological  hypertrophy  of 
certain  muscles  under  abnormal  conditions  is  evidence  of  an 
inherent  or  innate  capacity  for  adaptive  response.  For  example, 
pathological  conditions  which  throw  extra  work  upon  the  heart 
are  often  followed  by  the  hypertrophy  of  the  heart  itself ;  and,  as 
these  conditions  are  abnormal  or  exceptional,  it  is  said  that  the 
capacity  of  the  heart  for  responding  to  them  cannot  be  due  to  the 
survival,  in  past  generations,  of  those  ancestors  whose  hearts  thus 
responded ;  but  a  moment's  thought  will  show  that  the  survival  of 
ever}'^  mammal  does  depend  upon  the  power  of  its  heart  to  re- 
spond to  increasing  demands  by  increasing  efficiency.  If  the  work- 
ing capacity  of  the  heart  did  not  keep  pace  with  the  growth  of  the 
"body,  no  mammal  could  grow  up,  but  growth  is  a  normal  process, 
common  to  all.  No  mammal  could  survive  the  great  changes  which 
take  place  in  the  circulation  before  and  at  the  time  of  birth,  if  the 
capacity  of  its  heart  for  doing  work  did  not  keep  pace  with  the 
normal  changes  in  the  amount  of  work  which  is  required.  As  we 
have  already  seen,  page  ii,  that  the  responsive  activities  of  liv- 
ing things  may  be  called  out  by  either  the  normal  stimulus  or  any 
other  which  acts  in  the  same  way,  the  pathological  hypertrophy 
of  the  heart  is  no  more  than  the  past  history  of  mammals  would 
lead  us  to  expect. 

Improvement  of  our  muscles  under  exercise  is  the  outcome  of 
structural  adjustments  for  bringing  this  useful  end  about — it  is 
an  adaptation ;  and  the  heart  is  as  obviously  fitted  for  improve- 
ment by  use  as  it  is  for  propelling  blood.  Exercise  fits  a  muscle 
for  its  normal  work  only  so  far  as  structural  adjustments  for 
bringing  this  about  already  exist,  in  the  brain,  and  in  the  nervous 
system,  and  in  the  muscle  itself  ;  and  the  real  problem,  the  origin 
of  the  adaptation,  is  in  no  way  different  from  that  presented  by 
any  other  structural  adjustment. 

This  is  still  further  illustrated  by  the  fact  that  while  many 
organs  are  improved  by  normal  or  natural  use,  abnormal  or  un- 
natural use  is  well  called  abuse.  When  our  bodies  are  used  in 
what  is  popularly  called  the  way  they  were  intended  to  be  used, 
use  is  beneficial;  but  injudicious  or  excessive  training  may  be  as 
pernicious  as  neglect. 

If   we  acquire  no   nurture   except   that  which   our   nature   pro- 


68  THE  FOUNDATIONS   OF  ZOOLOGY 

vides  for,  what  are  we  to  say  of  the  acquisition  of  knowledge  ? 
Does  this  come  by  nature  and  not  by  nurture  ? 

The  use  of  language  is  an  acquired  art,  and  not  an  innate 
faculty.  Whitney  reminds  us  ("  Life  and  Growth  of  Language," 
p.  279)  that  "though  possessing  the  endowments  of  a  Homer 
or  a  Demosthenes,  no  man  can  speak  any  language  until  he  has 
learned  it,  as  truly  learned  it  as  he  learns  the  multiplication  table, 
or  the  demonstrations  of  Euclid." 

I  have  tried  to  show,  page  53,  that  since  each  vital  act  is  a 
response  to  a  sign  with  a  significance,  life  is  the  use  of  the 
language  of  natiire ;  and  it  follows,  if  this  phrase  is  to  be  taken 
literally,  that  life  is  an  acquired  art,  and  not  a  natural  inheritance. 
I  have  tried  to  show,  page  9,  that  this  may  be  the  case,  since  it  may 
be  the  adaptive  mechanism,  and  not  its  responsive  activity,  which  is 
inherited  from  parent  by  child. 

While  no  one  can  come  into  possession  of  a  language  without 
learning  it,  and  while  each  acquires  the  tongue  which  the  acci- 
dent of  birth  places  within  his  reach,  Whitney  reminds  us  that 
man  learns  language  because  "  he  possesses,  as  one  of  his  most 
marked  and  distinctive  characteristics,  a  faculty  or  capacity  of 
speech,  —  or,  more  accurately,  various  faculties  and  capacities  which 
lead  inevitably  to  the  production  of  speech ;  but  the  faculties  are 
one  thing,  and  their  elaborated  products  are  another  and  very 
different  one." 

"  It  needs  not  only  the  inward  power,  but  also  the  outward 
occasion,  to  make  man  what  he  is  capable  of  becoming." 

This  is  no  place  for  a  treatise  on  human  knowledge,  but  I 
think  that  the  mind  to  know  truth  seems,  to  most,  as  essential  as 
truth  to  be  known ;  for  it  does  not  seem  good  common  sense  to 
attribute  our  minds  to  either  the  direct  or  the  indirect  effects  of 
knowledge.  The  general  opinion  seems  to  be  that  our  minds 
come  by  nature,  rather  than  by  nurture,  although  some,  who 
admit  that  our  minds  are  ours  by  nature,  strangely  suppose  that 
these  same  minds  may  be  efficient  causes  of  changes  in  our 
nature. 

It  is  legitimate  and  relevant  to  ask  the  difificult  question 
whether  natural  knowledge  is  the  discovery  of  truth,  or  only  the 
avoidance    of   error;    and   there   is    much    to    be    said    in    favor   of 


NATURE  AND   NURTURE  6g 

Berkeley's  assertion,  that  "  the  work  of  science  is  to  unravel  our 
prejudices  and  mistakes,  untwisting  the  closest  connections,  distin- 
guishing things  that  are  different ;  instead  of  confused  and  per- 
plexed, giving  us  distinct  views;  gradually  correcting  our  judgment 
and  reducing  it  to  a  philosophical  exactness." 

Physical  exercise  corrects  our  bodily  movements,  and  reduces 
them  to  exactness,  by  giving  us  distinct  movements,  instead  of 
confused  and  perplexed  ones ;  but  we  are  unable  to  believe  that 
training  gives  us  any  new  muscles,  and  their  fitness  for  improve- 
ment by  exercise  is  itself  an  adaptation  which  calls  for  explana- 
tion. 

If  Berkeley  is  right,  as  he  seems  to  me  to  be,  and  if  what  we 
call  natural  knowledge  is  no  more  than  the  correction  of  our 
judgment  and  its  reduction  to  exactness,  it  seems  clear  that 
knowledge  no  more  accounts  for  our  judgment  than  training  ac- 
counts for  our  muscles,  and  that  physical  culture  and  mental  cult- 
ure are,  in  this  respect,  exactly  alike. 

The  modern  zoologist,  who  reflects  upon  the  phenorhena  of 
nature,  is  forced,  like  all  who  have  gone  before  him,  to  consider 
anew  the  ancient  and  difficult  question  whether  there  are  "  innate 
ideas";  and,  even  if  his  success  be  slight,  and  his  conclusions 
indefinite,  he  may,  perhaps,  make  use  of  his  acquaintance  with 
living  things  to  focus  the  point  at  issue,  and  to  show  that  this 
may  be,  in  part  at  least,  a  matter  of  words  and  definitions. 

"It  is  Plato's  remark,  in  his  'Theaetetus,'  that  while  we  sit  still 
we  are  never  the  wiser,  but  going  into  the  river,  and  moving  up  and 
down,  is  the  way  to  discover  its  depths  and  shallows.  If  we  exercise 
and  bestir  ourselves,  we  may  even  here  discover  something."  ^ 

So  far  as  it  concerns  the  zoologist,  the  question  seems  to  be  this : 
Is  it  something  we  find  in  our  nature,  or  something  we  discover  in 
the  outer  world,  which  justifies  our  confidence  in  our  mental  states 
and  in  our  responsive  actions ;  or  may  there  not  be  a  sense  in  which 
each  point  of  view  is  the  true  one  ? 

I  have  tried  to  show,  page  59,  that,  while  the  responsive  activities 
of  living  things  do  not  take  place  until  they  are  called  forth  by  a 
proper  stimulus,  the  things  they  do  under  stimulus  are  no  more  than 
their  organic  mechanism  would  lead  us  to  expect ;  and  that  there 

1  Berkeley,  "  Siris,"  p.  367. 


70  THE  FOUNDATIONS   OF  ZOOLOGY 

need  be  no  necessary  antagonism  between  those  who  attribute  the 
development  of  the  germ  to  mechanical  conditions  and  those  who 
attribute  it  to  the  inherent  potency  of  the  germ  itself. 

We  must  now  ask  whether  there  is  any  more  necessary  antag- 
onism between  those  who  attribute  knowledge  to  experience  and 
those  who  attribute  it  to  our  innate  reason. 

If  this  question  could  be  considered  in  itself,  it  might  not  be 
formidable ;  but  it  is  hedged  about  with  complications,  for  some  of 
which  the  modern  zoologist  is  responsible,  although  only  a  few  of 
the  perplexities  by  which  his  efforts  are  beset  can  be  laid  to  his 
own  charge. 

Some  zoologists  tell  us  that  the  value  of  our  responses  is  equiva- 
lent to  confidence  in  their  value,  although  it  is  clear  that  our  hearts 
had  value  before  men  studied  anatomy,  and  that  digestion  was 
useful  to  them  before  they  knew  that  it  occurs. 

We  are  also  told,  in  effect,  that  confidence  in  the  value  of  our 
mental  states  is  the  same  as  judicious  confidence  in  their  value, 
although  we  all  know  that  while  one  who  has  led  an  uneventful 
life  may  dread  all  accidents,  a  life  of  adventure  may  teach  that, 
while  some  accidents  are  to  be  avoided  at  any  cost,  the  danger  from 
others  is  trifling.  The  confidence  of  the  man  with  little  experience 
is  no  less  strong  than  that  of  the  adventurer,  but  it  is  less  judicious ; 
and,  as  we  use  words,  we  do  not  call  it  knowledge,  but  "  ignorant " 
prejudice,  or  "  unreasoning  "  cowardice,  although  there  is  no  reason 
why  those  who  wish  should  not  use  words  in  some  other  sense. 

The  question  whether  experience  is  or  is  not  the  only  source  of 
knowledge  clearly  turns,  in  part  at  least,  on  our  definition  of  know- 
ledge. An  infant  who  has  never  known  a  tumble  may  act  as  they 
act  who  know  the  danger  of  a  fall,  and,  if  response  to  the  order  of 
nature  were  evidence  of  knowledge,  it  would  be  obvious  that  some 
knowledge  is  innate,  or  independent  of  experience ;  but  it  is  not  our 
custom  to  call  the  blind  prejudice  of  ignorance  and  the  prudent 
conservatism  of  the  wise  by  the  same  name. 

Some  zoologists  hold  that  beneficial  response  to  a  stimulus  is 
evidence  that  the  stimulus  is  perceived,  and  that  the  response  is 
made  with  knowledge,  and,  if  this  were  admitted,  it  would  be  clear 
that  some  knowledge  is  innate  in  living  things ;  for  all  admit 
that  they  may  respond  to  the   order  of  nature  without  experience, 


NATURE  AND  NURTURE  y\ 

although  few  assert  that  every  response  is  evidence  of  knowledge. 
The  impulse  to  eat  when  we  are  hungry  is  useful,  but  we  do  not 
call  it  knowledge,  although  we  do  give  this  name  to  the  physiology 
which  tells  us  when  and  how  far  food  is  beneficial ;  and  we  distin- 
guish our  innate  "moral  sense"  from  knowledge  of  good  and  evil. 

We  are  sometimes  told  by  those  who  are  not  zoologists,  that, 
admitting  that  all  the  responsive  actions  of  living  things  may  be 
useful,  rational  responses  may  nevertheless  be  distinguished,  by 
perfectibility,  from  fixed  instincts  and  blind  mechanical  reflex  acts. 
It  is  said  that  while  mechanical  responses  are  persistent,  those  which 
are  due  to  knowledge  are  improvable ;  but  no  zoologist  can  admit 
that  any  property  of  living  things  is  immutable,  or  that  perfecti- 
bility is  evidence  of  knowledge.  If  the  correction  of  our  natural 
responses  and  their  gradual  reduction  to  exactness  by  the  suppres- 
sion of  those  which  are  confused  and  perplexed,  and  the  survival 
of  those  which  are  distinct  and  useful  were  evidence  of  knowledcre. 
might  not  the  zoologist  ask,  in  this  case,  whether  the  whole  history 
of  the  origin  of  species  by  means  of  natural  selection  may  not  be 
a  history  or  the  acquisition  of  knowledge  ?  For  it  is  a  history  of 
the  acquisition  of  something  which  our  reason  approves,  even  if 
we  are  quite  unable  to  tell,  in  most  cases,  whether  it  is  accompanied 
by  mind  or  not.  Whether  perfectibility  be  held  to  be  evidence  of 
knowledge  or  not,  may  not  the  zoologist  ask  if  the  question  whether 
knowledge  is  or  is  not  innate  may  not  depend  upon  the  answer  we 
give  to  the  farther  question  whether  it  is  the  activity  of  the  organic 
mechanism,  or  only  the  mechanism  itself,  that  is  transmitted  from 
parent  to  child ;  for  if  no  act  is  inherited,  is  it  not  hard  to  see  how 
there  can  be  any  innate  or  hereditary  knowledge } 

No  one  who  has  propagated  plants  from  cuttings  or  seen  a  sea- 
anemone  divide  into  two,  can  ask  whether  a  material  organism  may 
be  multiplied ;  but  they  who  hold  that  actions  may  be  transmitted 
and  multiplied  by  inheritance  seem  to  hold  that  the  law  of  the  con- 
servation of  energy  does  not  here  hold  good.  While  all  who  hold 
that  this  law  is  empirical  and  experimental  must  stand  ready  to  admit 
exceptions  to  it  when  proved,  he  must  be  of  bold  mind  who  holds 
that  inheritance  is  an  exception ;  and  we  have  already,  page  59, 
examined  evidence  which  seems  to  show  that,  while  the  things  which 
living  beings  do  under  stimuli  are  no  more  than  their  nature  would 


72  THE  FOUNDATIONS   OF  ZOOLOGY 

lead  one  to  expect,  we  have  no  reason  to  expect  these  things  to  take 
place  in  the  absence  of  these  stimuli  or  some  equivalent. 

If  the  believer  in  innate  ideas  tells  us  all  this  is  quite  con- 
sistent with  his  principles;  if,  while  admitting  that  he  knows  no 
mental  act  or  state  without  physical  concomitants,  he  assert  that 
the  subjective  or  mental  aspects  of  our  responsive  actions  arise 
in  us  because  of  our  inherent  nature ;  if  he  tell  us  that  the  physi- 
cal concomitants  are  only  the  "  occasion  "  of  the  mental  states,  or 
the  stimulus  under  which  they  arise  in  our  minds,  —  I  do  not  see 
why  the  zoologist  should  not  agree,  and  admit  that  he  is,  to  this 
extent,  an  intuitionist  after  the  ancient  school  of  Plato ;  for,  so 
far  as  science  tells  us,  what  we  call  the  "causes"  of  physical 
events  are  no  more  than  "occasions."  In  physical  science  all 
we  mean,  when  we  say  we  understand  a  thing,  is  that,  certain 
conditions  or  occasions  being  given,  it  may  be  counted  on  with 
confidence,  while  we  cannot  judiciously  expect  it  in  their  absence. 

The  question  at  issue  between  the  Lamarckian  and  the  Dar- 
winian is  not  whether  knowledge  arises  in  the  mind  in  the 
absence  of  experience,  but  whether  experience  is  anything  more 
than  the  "  physical  cause,"  or  occasion,  or  stimulus,  in  the  pres- 
ence of  which  knowledge  may  be  expected  to  arise  in  the  mind, 
and  in  the  absence  of  which  it  cannot  reasonably  be  looked  for. 
If  this  latter  is  the  case,  is  it  not  hard  to  see  how  experience 
can  be  either  the  efficient  or  the  physical  cause  of  the  mind  in 
which  it  arises } 

It  is  hard  to  calmly  ask  whether  training  and  education  and 
experience  add  anything  to  our  nature,  for  we  know  that  a  man 
educated  is  different  from  the  same  man  uneducated.  If,  at  first 
thought,  the  question  seems  repugnant  to  common  sense,  we 
must  remember  that  it  is  also  hard,  when  looking  through  a  bit 
of  colored  glass  at  a  neutral  wall,  to  believe  that  no  color  is 
added,  and  that  the  effect  is  due  to  negative  and  passive  ex- 
clusion by  selection  or  sifting. 

The  assertion  that  there  is  no  more  redness  on  the  wall,  or 
on  the  retin^.,  than  there  was  before  the  red  glass  was  interposed, 
seems,  at  first,  to  be  contradicted  by  our  sensations,  and  repug- 
nant to  common  sense. 

Who  can  imagine  more  color  outside  the   limits   of    a   rainbow 


NATURE  AND  NURTURE  73 

than  within  the  borders  of  the  arch  ?  When  the  rich  colors  of 
evening  spread  over  the  glowing  clouds,  after  a  dull,  gray  day, 
we  feel  that  new  wealth  of  beauty  has  been  added  at  the  end, 
and  that  the  dying  day  has  taken  on  new  splendors,  which  were 
absent  in  our  working  hours. 

The  emotional  value  of  nature,  and  its  moral  influence,  gain 
so  much  strength  as  the  day  dies,  that  the  impression  of  a  cor- 
responding gain  in  sensible  value  is  irresistible,  and  effort  to 
imagine  all  this  glorious  color  in  the  common  light  of  day  is 
vain;  yet  there  are  more  rays  of  crimson  and  red  and  purple  at 
noonday  than  in  the  declining  light  of  evening. 

One  modern  zoologist  has  defined  life  as  "memory";  and 
while  Plato's  belief  that  learning  may,  in  effect,  be  reminiscence 
seems  repugnant  to  common  sense,  the  zoologist  must  hold  it  an 
approximation  to  the  truth ;  although  he  cannot  forget  that,  so  far 
as  natural  selection  is  a  physical  explanation  of  the  "  archetype," 
or  species,  of  which  the  germ  becomes  reminiscent  in  develop- 
ment, just  so  far  is  it  a  physical  explanation  of  those  "forms," 
or  "  necessities  of  intellect,"  of  which  the  "  soul "  becomes  remi- 
niscent in  knowledge ;  for  improvement  under  experience  is,  as 
much  as  embryonic  development,  a  part  of  the  life  history  of 
a  normal  human  being. 

We  are  told  that  "  it  is  a  maxim  of  the  Platonic  philosophy 
that  the  soul  of  man  was  originally  furnished  with  native  inborn 
notions,  and  stands  in  need  of  sensible  occasions,  not  absolutely 
for  producing  them,  but  only  for  awakening,  rousing,  or  exciting 
into  act  what  was  already  preexistent,  dormant,  and  latent  in  the 
soul;  as  things  are  said  to  be  laid  up  in  the  memory,  though 
not  actually  perceived  until  they  happen  to  be  called  forth  and 
brought  into  view  by  other  objects." 

The  zoologist  of  our  day  may  ask  whether  all  that  the  living 
organism  does  may  not  be  latent  in  its  physical  organization, 
ready  to  be  called  forth  by  that  "  sensible  occasion "  which  we 
now  call  a  stimulus ;  although,  when  pressed  for  an  exhaustive 
definition  of  latent  potency,  he  may  find  no  better  answer  than 
an  admission  that  these  words  are  no  more  than  a  generalized 
statement  of  his  observations  on  the  actions  of  living  things  in 
general,    and   on   the    operations    of    his    own    mind    in    particular, 


74  THE  FOUNDATIONS   OF  ZOOLOGY 

joined  to  an  expression  of  his  confidence  that  these  observations 
may  be  repeated,  and  are  no  more  than  might  have  been  expected. 

When  the  believer  in  innate  ideas  goes  farther  than  this,  and 
asserts  that  the  "forms"  or  "archetypal  ideas"  which  thus  arise 
in  the  mind  are  universal  or  necessary,  the  zoologist  must  ask 
him  how  this  is  known.  Things  that  are  innate,  or  natural,  are 
not  always  universal  or  necessary,  for  while  parental  affection  is 
natural,  some  parents  are  unnatural. 

If  the  believer  in  innate  ideas  asserts  that,  while  our  latent  or 
potential  sensational  knowledge  does  not  become  active  or  mani- 
fest until  it  is  called  forth  by  some  change  in  the  physical  world, 
we  are  the  ultimate  and  efficient  causes  of  our  own  thoughts,  the 
zoologist  must  ask,  once  more,  how  this  is  known.  If  any  assert 
that  we  know  that  our  thoughts  are  ours  because  we  can  control 
them,  the  physiologist,  while  admitting  the  control,  asks  how  we 
know  that  the  way  we  control  them  is  different  from  the  way  we 
control  our  visual  sensations  by  going  into  a  dark  room,  or  by 
shutting  our  eyes. 

All  admit  that  all  normal  human  beings  who  are  not  helpless 
infants,  or  aged  dotards,  are  able  to  control  their  thoughts,  and 
the  actions  which  follow  them,  in  some  practical  sense  of  the 
words. 

"  If  I  take  things  as  they  are  and  ask  any  plain,  untutored  man 
whether  he  acts  or  is  free  in  any  particular  action,  he  readily 
assents,  and  I  as  readily  believe  him  from  what  I  find  within. 
And  if  man  be  free,  he  is  plainly  accountable.  But  if  you  shall 
define,  abstract,  suppose,  and  it  shall  follow  that  according  to  your 
definitions,  abstractions,  and  suppositions,  there  can  be  no  free- 
dom in  man,  and  you  shall  therefore  infer  that  he  is  not  account- 
able, I  shall  make  bold  to  depart  from  your  metaphysical  abstract 
sense  and  appeal  to  the  common  sense  of  mankind." 

May  not  the  modest  zoologist,  who  humbly  admits  that,  while 
he  does  not  know  what  the  relation  between  mind  and  matter 
is,  he  would  like  to  find  out,  also  ask,  in  all  sincerity,  whether  it 
is  he  who  has  perplexed  our  common  sense  by  defining  and  ab- 
stracting and  supposing .''  May  he  not  also  ask,  not  in  a  critical 
spirit,  but  in  order  that  he  may  approach  this  difficult  subject 
without    prejudice,    whether    some    of    the    responsibility    for    this 


NATURE  AND  NURTURE  75 

perplexity  may  not  be  laid  to  the  charge  of  those  metaphysicians 
and  theologians  and  philosophers  who  have  told  him  that  actions 
which  are  mechanical  cannot  be  free,  because  they  are  necessary  ? 

When  we  control  our  visual  sensations  by  shutting  our  eyes, 
we  employ  physical  means,  and  while  one  who  is  thus  enabled 
to  control  some  of  his  mental  states  by  physical  means  may  also 
be  able  to  use  these  means  or  not  as  he  chooses,  how  can  this 
be  evidence  that  his  ability  is  independent  of  physical  means  ? 

Is  it  necessary  to  know  what  the  relation  between  mind  and 
matter  is,  in  order  to  study  mind  ?  As  we  know  what  we  mean 
by  a  plant,  and  may  study  botany,  without  knowing  when  or  how 
plants  become  differentiated  from  animals,  and  without  knowing  any 
absolute  diagnosis  of  a  plant,  so,  too,  may  we  not  study  know- 
ledge, without  knowing  when  or  how  it  becomes  differentiated  from 
instinct  and  impulse  and  emotion  and  unperceived  cerebration  ? 

As  we  use  the  words,  is  knowledge  equivalent  to  response, 
or  to  beneficial  response,  or  to  the  improvement  of  response,  or 
to  response  which  is  immediately  controlled  ?  Is  it  not  rather 
the  correction  of  our  judgment  and  its  reduction  to  exactness  ? 
Whether  knowledge  is  innate  or  not,  does  any  one  believe  that 
our  judgment  is  ever  corrected  without  a  "sensible  occasion"? 
May  not  the  amount  of  this  correction  be  measured  by  experi- 
ence ?  If  what  we  mean  by  knowledge  is  the  correction  of  our 
judgment  under  the  stimulus  of  experience,  is  it  not  idle  to  ask 
whether  we  may  have  knowledge  without  experience,  for  is  not 
this  a  contradiction  in  terms  ?  If  any  choose  to  define  knowledge 
as  response,  and  to  thus  use  the  word  consistently,  no  one  need 
object,  for  words  are  conventional  symbols,  which  change  their 
meaning  continually,  although  no  one  who  uses  common  words 
in  an  uncommon  way,  without  defining  them,  can  hope  to  be 
understood. 

We  are  told  that  if  the  "  Lamarckian  factors "  are  in  any 
degree  operative  at  all,  their  great  function  "  must  be  that  of 
supplying  to  natural  selection  the  incipient  stages  of  adaptive 
modification,  in  all  cases  where,  but  for  this  agency,  there  would 
be  nothing  of  the  kind  to  select";  but  unless  these  "factors" 
can  be  proved  to  have  this  function,  they  are  unworthy  of  con- 
sideration as  a  contribution  to  the  history  of  adaptive  modification. 


76  THE  FOUNDATIONS  OF  ZOOLOGY 

I,  for  one,  have  found  little  to  interest  me  in  the  interminable 
dispute  as  to  the  inheritance  or  non-inheritance  of  the  effects  of 
the  conditions  of  individual  life,  because  the  gist  of  the  whole 
matter  has  seemed  to  me  to  lie  in  the  deeper  question  whether 
these  effects  are  inherently  adaptive ;  and  I  am  forced  to  ask  for 
evidence  that  the  "  Lamarckian  factors"  can  give  rise  to  even  the 
incipient  stages  of  adaptive  modification,  before  I  care  to  inquire 
whether  they  are  or  are  not  inherited.  We  are  told  that,  "  Inas- 
much as  we  know  to  what  a  wonderful  extent  adaptive  modifica- 
tions are  secured  during  individual  lifetime,  by  the  direct  action 
of  the  environment  on  the  one  hand,  and  by  increased  or  dimin- 
ished use  of  special  organs  and  mental  faculties  on  the  other,  it 
becomes  obvious  of  what  importance  even  a  small  measure  of 
transmissibility  on  their  part  would  be,  in  furnishing  to  natural 
selection  ready  made  variations  in  required  directions,  as  distin- 
guished from  promiscuous  variations  in  all  directions." 

This  a  priori  argument  to  prove  that  the  effect  of  these 
"factors"  must  be  inherited,  because  if  so,  it  would  be  so  useful, 
has  seemed  plausible  to  many ;  but  its  fallacy  is  clear,  unless  the 
inheritance  of  nurture  can  be  proved  to  be  beneficial  prior  to  selec- 
tion ;  for,  while  the  ways  to  use  our  bodies  and  our  faculties  are 
few  and  definite,  the  ways  to  abuse  them  are  innumerable ;  and 
the  inheritance  of  all  the  effects  of  the  conditions  of  life  would 
seem  more  likely  to  lead  to  cumulative  destruction  than  to  cumu- 
lative adaptation.  Unless  the  "  Lamarckian  factors  "  can  be  shown 
to  have,  prior  to  selection,  a  determinate  influence  in  beneficial 
lines,  it  seems,  on  the  whole,  rather  fortunate  than  otherwise  that 
evidence  of  the  inheritance  of  their  effects  is  so  hard  to  find. 

When  bodily  structure  is  improved  and  developed  by  use,  we 
find  structural  adjustments,  which  themselves  require  explanation, 
for  bringing  this  useful  end  about ;  nor  does  there  seem  to  be 
any  reason  to  believe  the  case  is  any  different  when  intellectual 
and  moral  improvement  are  in  question.  Here,  as  elsewhere,  we 
are  benefited  by  training  and  practice  and  education  because  our 
nature  fits  us  for  improvement  by  judicious  nurture. 

Capacity  for  individual  development  and  improvement,  muscu- 
lar or  mental  or  moral,  under  the  normal  conditions  of  life,  is  an 
adaptation,  —  by  far  the  most  wonderful  and  admirable  of  adapta- 


NATURE  AND  NURTURE  77 

tions,  —  and  the  beneficial  influence  of  the  "  Lamarckian  factors," 
so  far  as  this  influence  is  beneficial,  is  not  an  explanation,  but  a 
fact,  that  itself  calls  for  explanation. 

Is  there  any  evidence  that  the  influence  of  nurture  is  inherently 
beneficial  ?  If  there  is  not,  must  we  not  believe  that  all  its  effects, 
except  those  which  result  from  preexisting  adaptive  nature,  will 
be  haphazard,  so  far  as  their  fitness  for  the  needs  of  living  things 
is  in  question  ?  Will  they  not  be  identical  with  what  Darwin  has 
called  "fortuitous  variation"? 

It  scarcely  seems  necessary  to  point  out,  at  this  late  day,  that 
Darwin's  assertion  that  an  event  is  "  fortuitous  "  is  not  to  be  inter- 
preted as  belief  that  it  is  due  to  Chance,  or  that  it  is  out  of  the 
chain  of  natural  causation.  If,  with  Aristotle,  we  say  the  rain 
does  not  fall  to  make  the  farmer's  corn  grow,  any  more  than  it 
falls  to  spoil  his  corn,  all  we  mean  is  that  we  discover  no  connec- 
tion between  the  physical  causes  of  the  shower  and  the  farmer's 
needs. 

Few  are  bold  enough  to  assert  that  what  we  fail  to  discover 
does  not  exist,  although  all  must  admit  that  it  explains  nothing. 

The  hypothesis  that  the  rain  falls  to  spoil  the  farmer's  corn  is 
inadmissible,  not  because  we  know  it  to  be  untrue,  but  because  we 
find  no  evidence  of  its  truth,  and  no  value  in  its  practical  applica- 
tion. If,  in  the  absence  of  an  adaptive  nature,  we  find  no  con- 
nection between  the  effects  of  nurture  and  the  needs  of  living 
things,  then  nurture  is  fortuitous,  so  far  as  we  are  concerned,  as 
an  explanation  of  adaptive  structure. 

So  far  as  I  can  see,  there  is  no  a  priori  reason  why  nurture 
might  not  give  rise  to  adaptive  structures,  as  perfect  and  admi- 
rable as  the  heart  or  the  eye,  although  we  find,  as  a  matter  of  fact, 
that  injurious  nurture  is  just  as  compatible  with  the  system  of 
things  as  beneficial  nurture.  Nor  is  the  difficulty  at  all  diminished 
by  the  belief  that  a  necessary  law  of  universal  progress  or  evolu- 
tion gives  to  nurture  a  beneficent  impetus ;  for  men  of  science 
repudiate  the  opinion  that  natural  laws  are  rulers  and  governors 
over  nature ;  looking  with  suspicion  on  all  "  necessary "  or  "  uni- 
versal "  laws. 

The  production  of  words  and  sentences  and  great  works  of 
literature   and  science,  by   running  type  through  a  hopper,  is   not 


78  THE  FOUNDATIONS  OF  ZOOLOGY 

impossible,  and,  in  the  long  history  of  living  things,  adaptive  struct- 
ures may  have  been  produced,  without  selection,  by  the  fortuitous 
coincidence  of  fortuitous  variations,  but  many  generations  of  readers 
have  approved  Swift's  assertion  that  the  attempt  to  advance  know- 
ledge by  turning  a  crank  failed  to  produce  a  single  learned  treatise. 
The  presumption  against  the  production  of  adaptations,  incipient 
or  otherwise,  by  nurture,  seems  so  overwhelming  that  we  are  justi- 
fied in  demanding  demonstrative  evidence,  before  we  accept  this 
explanation  of  any  adaptation. 

They  who  think  that  the  "inheritance  of  acquired  characters" 
must  be  a  factor  in  organic  evolution,  because  we  find,  in  living 
nature,  so  much  that  we  cannot  yet  explain  without  it,  would  do 
well  to  ask  themselves  whether  it  would,  after  all,  help  them  out 
of  any  of  their  difficulties,  even  if  its  occurrence  were  proved.  If 
this  is  the  case,  would  they  not  do  well  to  rest  on  their  oars,  and 
to  look  about  them  .-•  For  that  which  they  are  in  search  of  may 
prove  to  be  plainly  in  the  sight  of  those  who  have  the  eyes  to  see. 

An  English  writer  has  recently  formulated  what,  he  tells  us,  is 
the  Lamarckian  answer  to  this  sort  of  reasoning.  He  says :  "  The 
assimilation  and  growth  of  a  muscle  under  stimulus  must  be  as- 
cribed to  a  fundamental  property  of  protoplasm,  which  it  is  not 
the  business  of  Lamarckians  or  evolutionists  of  any  other  school 
to  explain." 

"  According  to  the  Lamarckian  view  all  adaptations,  at  any 
rate  all  adjustments  concerning  whose  action  and  efficacy  there  is 
no  dispute,  have  arisen  in  the  same  way  as  the  enlargement  of  a 
muscle  by  exercise;"  and,  whereas  "Brooks  supposes  that  these 
structural  adjustments  have  to  be  explained,  Lamarckians  suppose 
they  are  merely  the  fundamental  properties  of  protoplasm." 

As  this  writer  also  says  "  Brooks  has  quite  failed  to  understand 
the  Lamarckian  view,"  I  shall  not  attempt  to  interpret  his  belief 
that  such  an  adaptation  as  the  fitness  of  the  eye  for  vision,  con- 
cerning whose  action  and  efficacy  there  does  not  seem  to  be  any 
dispute,  is  tnerely  a  property  of  protoplasm ;  and  I  shall  content 
myself  with  the  admission  that  he  is  quite  right  in  asserting  that 
Brooks  supposes  this  fitness  has  to  be  explained  if  it  can  be.  He 
may  be  pleased,  however,  to  know  that  a  still  shorter  way  with  the 
Darwinian  would  be  to  ascribe  all  things  to  the  cosmic  vapor,  and. 


NATURE  AND  NURTURE  79 

closing  our  laboratories  and  observatories,  to  rest  content  with  the 
assertion  that  things  like  those  which  distinguish  men  from  turnips 
are  merely  the  fundamental  properties  of  primitive  nebulosity. 

If  I  understand  this  author,  he  believes  the  attributes  of  all 
living  things  are  deducible  from  the  properties  of  protoplasm ;  and 
as  I  myself  believe  nothing  inconsistent  with  this  creed,  except 
that  the  assertion  which  outstrips  evidence  is  a  crime,  I  am  quite 
ready  to  agree  with  him  when  he  has  deduced  such  things  as  his 
logic,  for  example,  from  protoplasm ;  although,  if  an  Americanism 
may  be  permitted,  his  assertion  seems  a  little  prcvio7is. 

After  this  has  been  proved,  if  it  ever  is  proved,  it  seems  clear 
that  it  will  hold  true  of  the  properties  of  the  unsuccessful,  the 
unfit,  and  the  exterminated,  as  well  as  those  of  the  fit ;  and  that 
the  problem  of  fitness  will  still  be  as  it  was. 

This  problem  is  real.  By  recognizing  and  boldly  facing  it 
Darwin  and  Wallace  succeeded  in  making  one  of  the  greatest 
strides  in  the  whole  history  of  human  thought;  and  I  must  refuse 
to  admit  that  any  good  thing  can  come  from  a  denial  of  its  exis- 
tence, or  from  the  creed  that  it  is  "universal"  and  beyond  the 
reach  of  science. 


LECTURE    IV 

LAMARCK 


"  Heaven  forfend  me  from  Lamarck  nonsense  of  a  tendency  to  progression,  adapta- 
tions from  the  slow  willing  of  animals,  etc.;  but  the  conclusions  I  am  led  to  are  not 
widely  different  from  his  ;  though  the  means  of  change  are  wholly  so.  I  think  I  have 
found  out  (here's  presumption !)  the  simple  way  by  which  species  become  exquisitely 
adapted  to  various  ends."  —  C.  Darwin  to  J.  D.  Hooker,  Jan.   ii,  1848. 

"  The  hypothesis  of  Lamarck  —  that  progressive  changes  in  species  have  been  pro- 
duced by  the  attempts  of  animals  to  increase  the  development  of  their  own  organs, 
and  thus  to  modify  their  structure  and  habits — has  been  repeatedly  and  easily  refuted 
by  all  writers  on  the  subject." — Wallace:  "On  the  Tendency  of  Varieties  to  depart 
indefinitely  from  the  Original  Type,"  Journ.  Proc.  Linnean  Soc."  August,  1858. 

"  The  Lamarckian  hypothesis  has  long  since  been  justly  condemned."  —  Huxley  : 
"Collected  Essays,"  H.,  p.   12,  1859. 

"  It  may  be  doubted  whether  Lamarck  has  not  suffered  more  from  his  friends 
than  from  his  foes."  —  HuXLEY :   "Collected  Essays,"  H.,  p.  69. 

"  Lamarck  assigned  partly  unreal,  partly  insufficient  causes ;  and  the  attempt  to 
account  for  a  progressive  change  in  species  through  the  direct  influence  of  physical 
agencies,  and  through  the  appetencies  and  habits  of  animals  reacting  upon  their  struct- 
ure, thus  causing  the  production  and  the  successive  modification  of  organs,  is  a  con- 
ceded and  total  failure."  —  Asa  Gray  :  "The  Origin  of  Species  by  Means  of  Natural 
Selection,"  Amer.   yournal  Science  and  Arts,  March,   i860. 


LECTURE    IV 

LAMARCK 

Conclusive  proof  of  the  inheritance  of  the  effects  of  the  direct 
action  of  the  conditions  of  life  may  be  found  at  any  moment,  for 
all  one  knows  to  the  contrary ;  but  even  if  they  who  are  acquainted 
with  no  positive  evidence  think,  with  the  writer,  that  a  dogmatic 
assertion,  from  negative  evidence,  or  in  the  absence  of  all  evidence, 
that  these  effects  are  not  inherited,  or  cannot  be  inherited,  would 
be  rash  and  unscientific,  they  may,  nevertheless,  be  interested  in 
an  attempt  to  test  the  value  of  the  assumption  that  they  are  inher- 
ited ;  admitting,  in  the  interest  of  clear  thinking,  that  the  assump- 
tion is  reasonable  and  admissible. 

That  "  inheritance  of  acquired  characters  "  might  produce  some 
system  of  living  nature  seems  probable ;  if  we  start  with  organisms 
with  such  constitution  that  this  "  factor  "  tends  to  produce  modifi- 
cations which  are  both  adaptive  and  inherited.  That  it  has  not 
produced,  or  materially  aided  in  producing,  the  system  which  we 
know  seems  certain. 

Our  business  is  to  study  that  which  is,  not  that  which  might 
be ;  and  I  shall  try  to  show,  as  it  has  been  shown  again  and  again, 
that  the  adjustments  which  are  exhibited  by  living  things  are  such 
as  to  show  that  the  "  inheritance  of  acquired  characters  "  has  played 
no  essential  part  in  their  production. 

The  most  extreme  Lamarckian  must  admit  that  no  organism  can 
transmit  or  inherit  modifications  produced  by  the  conditions  of 
any  life  except  its  own,  or  that  of  its  ancestors.  The  nurture 
of  A  cannot  be  transmitted  by  B;  nor  can  it  be  part  of  the  inherited 
nature  of  B's  descendants  unless  they  are  also  descended  from  A. 
How,  then,  are  we  to  explain  such  things  as  the  bee's  sting  or  the 

83 


84  THE  FOUNDATIONS   OF  ZOOLOGY 

poison  of  serpents,  —  things  which  are  useful  only  in  their  effect 
on  other  animals  than  the  user  ? 

How  are  we  to  explain  adjustments  to  the  life  of  other  beings 
than  the  ones  that  exhibit  the  adjustment? 

As  the  serpent  which  is  able  to  destroy  its  prey,  and  the  bee 
which  is  able  to  drive  away  its  enemies,  have  an  advantage  in  the 
struggle  for  existence,  it  is  easy  to  understand  how  these  powers  may 
have  arisen  through  selection  ;  for  the  bee's  sting  is  a  modified  ovi- 
positor, and  it  is  used  by  some  of  the  Hymenoptera  both  as  a 
weapon  of  defence,  and  as  an  organ  for  laying  the  eggs  in  the 
tissues  of  plants,  thus  exciting  pathological  changes  in  these  tissues, 
so  that  they  form  galls,  and  store  up,  around  the  eggs,  starch  to 
serve  as  food  for  the  larvae  which  hatch  from  the  eggs.  While  the 
origin  of  these  adjustments  by  selection  is  quite  intelligible,  there 
does  not  seem  to  be  any  other  way  to  account  for  them. 

The  white  upturned  tail  of  the  rabbit  is  a  danger-signal.  When 
disturbed  or  alarmed  on  the  feeding-ground,  which  they  visit  soon 
after  sunset  or  on  moonlight  nights,  the  rabbits  make  for  their 
burrows,  and  the  white  upturned  tails  of  those  in  front  serve  as 
guides  and  signals  to  those  more  remote  from  home,  to  the  young 
and  feeble ;  and  thus,  each  following  the  one  or  two  before  it,  all 
are  able,  with  the  least  possible  delay,  to  reach  a  place  of  safety. 

Many  defenceless  insects  are  protected  by  their  resemblance  to 
dangerous  animals,  or  by  some  threatening  or  unusual  appearance. 
The  great  green  caterpillar,  known  in  some  of  our  Southern  states 
as  the  "  hickory-horned  devil,"  has  an  immense  crown  of  orange- 
red  tentacles,  which,  if  disturbed,  it  erects  and  shakes  from  side 
to  side  in  a  manner  so  alarming  that  the  negroes  believe  it  is 
more  deadly  than  a  rattlesnake. 

Who  can  believe  that  the  inherited  effect  of  the  terror  it  excites 
has  modified  the  hickory-horned  devil .-'  After  giving  the  matter 
my  best  and  most  serious  thought,  I  am  unable  to  imagine  any  way 
in  which  the  effect  of  the  upturned  tail  of  the  hinder  rabbit  can  act 
upon  the  tail  of  the  rabbit  in  front,  or  any  way  by  which  the  sight 
of  the  tail  in  front  can  modify  the  tail  of  the  rabbit  behind.  I  find 
the  production  of  adaptations  of  this  sort  by  the  inheritance  of 
the  beneficial  effects  of  use,  or  in  any  way  except  by  selection,  quite 
unthinkable.     Most  pelagic   larvae  are   transparent,  even  when  the 


LAMARCK  85 

adults  are  beautifully  and  conspicuously  colored,  and  their  bodies 
are  often  drawn  out  into  long  spines  and  processes.  In  the  zoea 
of  Porcellana,  for  example,  these  spines  are  so  long,  as  compared 
with  the  body  proper,  that  this  zoea  when  seen  with  a  lens  reminds 
one  of  an  oarsman  seated  in  the  middle  of  a  very  long,  sharp-pointed 
glass  boat.  Often  the  spines  are  strengthened  by  calcareous  ladders 
formed  of  long  parallel  transparent  side-strips,  like  glass  threads, 
with  cross-bars  at  regular  intervals.  No  one  who  has  strained  his 
eyes  to  discover  in  a  glass  of  water  one  of  these  transparent 
larvae  which  he  has  captured,  and,  after  repeated  attempts  to  suck 
it  into  a  dipping-tube  for  study  under  the  microscope,  fails,  because, 
«ven  when  the  end  of  the  tube  is  at  last  brought  directly  over  it, 
it  catches  across  the  end  of  the  tube  and  permits  the  current  of 
water  to  rush  by  without  drawing  it  in,  can  doubt  that  the  transpar- 
ency of  pelagic  larvae  is  protective,  or  that  the  spines  and  processes 
keep  them  out  of  the  mouths  of  their  enemies,  just  as  a  long 
ladder  may  keep  the  man  who  carries  it  from  slipping  through  holes 
in  treacherous  ice. 

The  way  the  spines  of  a  zoea,  or  the  ladders  of  a  pluteus,  increase 
what  may,  figuratively,  be  called  the  angle  of  incidence,  is  so  clear 
that  few  students  of  marine  zoology  will  hesitate  to  make  still  farther 
use  of  the  language  of  the  mathematicians,  and  to  assert  that  the 
number  of  mouths  large  enough  to  swallow  a  pluteus  decreases 
inversely  as  the  square  of  the  angle  of  incidence. 

A  naturalist  was  stopped,  in  the  jungle  of  Java,  by  a  dense  bush, 
on  a  leaf  of  which  he  saw  a  butterfly  sitting  on  what  he  took  to  be 
a  bird's  dropping,  and,  as  he  had  often  wondered  at  this  habit,  he 
approached  with  gentle  steps  and  ready  net,  to  see,  if  possible,  how 
the  insect  was  engaged.  It  permitted  him  to  get  quite  close  and 
even  to  seize  it  with  his  fingers,  but  he  tells  us  that  to  his  delighted 
surprise  part  of  the  body  remained  behind,  adhering,  as  he  thought, 
to  the  excreta ;  but  looking  more  closely,  and  finally  touching  it 
with  his  finger,  he  found,  to  his  astonishment,  that  his  eyes  had 
been  most  perfectly  deceived,  and  that  what  seemed  to  be  the  ex- 
creta was  a  most  artfully  colored  spider,  lying  on  its  back  with  its 
feet  crossed  over  and  closely  pressed  to  its  body,  thus  producing  a 
living  bait  for  butterflies  and  other  insects  so  artfully  contrived  as 
to  deceive  a  pair  of  human  eyes,  even  when  intently  examining  it. 


86  THE  FOl/NDATIOJVS  OF  ZOOLOGY 

Who  can  believe  that  the  transparent  color  and  the  long  spines 
of  pelagic  larvae  have  been  produced  by  the  direct  action  of  these 
adjustments  upon  their  enemies?  When  we  remember  that  it  is 
not  the  spider  but  the  butterfly  which  is  deceived,  can  we  believe 
that  the  structure  and  habits  of  the  Java  spider  are  due,  either 
wholly  or  in  any  degree,  to  the  inheritance  of  the  effects  of  the 
deception  ? 

The  brilliant  colors  and  the  pleasant  fragrance  of  the  flower  are 
useful  to  the  plant,  or  at  least  to  its  species,  since  they  attract 
insects,  and  thus  fertilize  the  seeds,  and  provide  for  its  perpetuation. 

There  is  no  difficulty  in  understanding  how  these  useful  properties 
of  the  flower  may  have  arisen  by  selection ;  but  if  they  are  directly 
due  to  the  conditions  of  plant-life,  their  usefulness  must  be  acci- 
dental, for  no  one  has  any  reason  to  believe  that,  prior  to  selection, 
these  conditions  bear  any  relation  to  the  feelings  of  an  insect ;  nor 
can  we  believe  that  the  visits  of  an  insect  will  modify  the  color  or 
odor  of  a  flower  in  such  a  way  as  to  suit  the  insect's  taste,  except 
by  pure  accident ;  unless,  indeed,  we  choose  to  fancy  that  the  insect 
designedly  modifies  the  flower.  Even  if  this  hypothesis  be  admitted, 
it  does  not  help  the  matter,  unless  we  show  that  the  insect  intended 
to  modify  the  flower  in  such  a  way  as  to  benefit  the  plant. 

Some  may  possibly  be  able  to  believe  that  the  use  of  the  color 
and  perfume  of  the  plant  in  attracting  insects  is  accidental ;  but 
can  any  one  believe  this  of  the  complicated  and  delicate  machinery 
for  securing  insect-fertilization,  which  we  find  in  the  flowers  of 
orchids  .'' 

For  all  I  know,  the  Lamarckian  may  claim  that  the  visits  of 
insects  have,  in  some  way,  modified  the  flower,  to  its  own  good,  by 
their  mechanical  action,  by  pulling  down  this  part,  and  by  pushing 
up  that,  generation  after  generation,  until  they  have  caused  adap- 
tive modification  in  the  flower.  I  do  not  know  how  much  his 
ingenuity  may  be  able  to  make  out  of  this  hypothesis  ;  but  no  one 
can  believe  that  the  hooks  and  spines,  which  are  so  obviously 
adapted  for  distributing  burrs  and  seeds,  by  fastening  them  to  the 
fur  of  passing  mammals,  have  been  produced  by  the  inheritance  of 
the  effects  of  this  sort  of  mechanical  contact ;  for  these  structures 
do  not  come  into  use  until  they  are  dead  ;  and,  most  assuredly,  dead 
things  cannot  transmit  "  acquired  characters  "  to  their  descendants. 


LAMARCK  87 

When  a  drop  of  rain  or  dew  falls  on  the  dead,  dry,  twisted 
glume  of  the  animated  oat  {Avena  sterilis\  it  untwists  in  such  a 
way  as  to  push  like  the  leg  of  a  grasshopper,  and,  raising  the  seed, 
to  send  it  off  with  a  jump.  After  the  seed  has  fallen,  this  process 
is  repeated  again  and  again,  until  the  heavy  end,  where  the  seed  is 
placed,  falls  at  last  into  some  roughness  in  the  ground,  when  the 
glumes  begin  to  kick  and  to  struggle,  and,  catching  in  the  grass  and 
roots,  or  on  the  rough  ground,  to  push  the  seed  down  and  to 
plant  it. 

The  seed  is  alive,  but  the  glumes  are  dead  and  dry,  and  as  com- 
pletely out  of  the  line  of  descent  to  future  generations  as  the  dead 
leaves  which  drop  from  a  tree. 

Is  it  not  impossible  to  see  how  the  effects  of  the  use  of  dead  things 
can  be  transmitted  to  their  descendants  .-•  As  the  properties  of  the 
dead  glumes  are  as  useful  to  the  species  as  the  dead  sticks  with 
which  a  bird  builds  its  nest  are  to  the  nestlings,  is  it  any  harder  to 
see  how  the  power  to  produce  glumes  which,  after  they  are  dead, 
shall  have  this  useful  property,  may  have  arisen  through  selection, 
than  to  understand  that  an  annual  plant,  which  dies  before  its  seeds 
ripen,  may  have  thus  arisen .''  Many  organs  have  two  functions, 
one  accessory  to  the  other.  A  muscle  may  be  said  to  serve  its 
purpose  when  it  is  used;  and  the  opinion  that  its  continual  use  has 
brought  about,  or  helped  to  bring  about,  its  useful  structure,  has 
seemed  plausible  to  many ;  but  consider  organs  such  as  the  reproduc- 
tive organs.  They  are  useful  to  their  possessors  in  many  ways.  The 
normal  development  of  a  male  mammal  is  arrested  if  they  are 
removed ;  so  we  must  believe  that  this  normal  development  is  itself 
due  to  some  stimulus,  which  is  given,  by  these  organs,  to  all  parts  of 
the  body.  It  may  be  no  harder  to  imagine  the  development  of  the 
reproductive  organs  by  use,  than  it  is  to  imagine  the  development 
of  the  muscle  in  the  same  way;  for  these  organs  are  wonder- 
fully adapted  for  gratifying  one  of  the  most  intense  natural  passions 
of  their  possessors :  but  this  use  is  only  a  means  to  an  end ;  and  it 
is  evident  that  this  end,  an  offspring,  has  no  existence,  as  such,  when 
they  are  used.  Their  true  use  is  such  that  it  brings  to  the  user 
care  and  responsibility  and  loss  of  freedom,  or  even  suffering  and 
death. 

In  many  species,  sexual  union  ends  the  life  of  the  male ;  while 


S8  THE  FOUNDATIONS  OF  ZOOLOGY 

the  female  often  dies  in  the  act  of  laying  her  eggs.  To  most  ani- 
mals the  impulse  to  use  these  organs  comes  before  they  can  have 
any  experience  of  its  purpose,  and  the  fulfilment  of  this  purpose  is 
separated,  by  such  a  length  of  time,  from  the  act  of  use,  that  few 
animals  can  possibly  have  any  knowledge  of  the  relation  between  the 
two  events.  When  this  relation  is  most  clearly  understood,  we  find, 
instead  of  a  desire  to  increase  the  fitness  of  these  organs  for  their 
purpose,  a  well-marked  impulse  to  enjoy  the  gratification,  without 
the  burden  of  care  and  responsibility  which  comes,  in  course  of 
nature,  when  their  true  purpose  is  accomplished. 

How  can  the  Lamarckian  deal  with  a  case  like  this  where 
conscious  effort  is  ruled  out,  and  where  the  true  use  is  the  benefit  of 
a  being  which  was  not  in  existence  as  such  at  the  time  when  the 
organs  were  used  } 

The  same  thing  is  true  of  all  our  other  natural  passions  and 
appetites.  So  far  as  the  actions  to  which  they  lead  are  voluntary, 
they  are  attended  with  pleasure,  or  else  their  restraint  is  attended 
with  discomfort,  but  we  are  usually  quite  unconscious  of  their  real 
use,  until  this  is  discovered  by  the  indirect  methods  of  scientific 
inquiry.  Hunger  stimulates  the  animal  to  actions  which  satisfy  the 
calls  of  hunger ;  but  the  mere  satisfaction  of  hunger  is  of  no  use, 
and  the  real  function  of  the  digestive  organs,  the  nutrition  of  the 
tissues,  goes  on  in  unconsciousness. 

The  snake's  poisoned  fang  and  the  bee's  sting  and  the  perfume 
of  the  flower  are  useful,  but  the  useful  property  is  an  effect  on  other 
organisms  than  the  one  which  exhibits  the  adjustment.  If  any  one 
thinks  he  can  see  how  this  sort  of  adjustment  might  be  brought 
about,  or  even  essentially  aided,  through  the  inheritance,  by  one 
being,  of  the  influence  of  its  structure  on  another  being,  I  cannot 
reason  with  him ;  for  I  find  his  thesis  quite  unthinkable. 

It  is  most  important  to  note  that  this  is  not  a  special  plea,  based 
upon  exceptional  cases.  I  have  called  attention  to  these  examples 
because,  far  from  being  exceptions,  they  are  simple  and  obvious 
illustrations  of  a  general  law,  for  all  of  the  adaptations  of  nature  are 

of  this  sort. 

In  all  cases,  the  structure,  habits,  instincts,  and  faculties  of  living 
things,  from  the  upward  growth  of  the  plumule  of  the  sprouting 
seed  to  the  moral  sense  of  man,  are  primarily  for  the  good  of  other 


LAMARCK  89 

beings  than  the  ones  that  manifest  them ;  and  there  is  nothing 
anomalous  or  -  exceptional  in  either  the  poison  of  serpents  or  the 
organs  of  reproduction,  or  in  the  altruistic  moral  sense  of  man. 

The  conditions  of  life  can  stand,  prior  to  selection,  in  no  causal 
relation  to  the  life  of  any  being  except  the  one  on  which  they  act ; 
but  no  fact  in  nature  is  more  incontestable  than  the  insignificance  of 
the  individual,  as  compared  with  the  welfare  of  the  species.  While 
this  has  no  existence  apart  from  the  series  of  individuals  which  com- 
poses it,  the  individual  counts  for  nothing  in  nature  while  the  species 
is  supreme. 

The  contrast  between  what  we  may  call  the  solicitude  of  nature 
to  secure  the  production  of  new  beings,  and  the  ruthlessness  with 
which  they  are  sacrificed  after  they  have  come  into  existence,  is  a 
stumbling-block  to  the  Lamarckian,  and  the  crowning  glory  of 
natural  selection  is  that  it  solves  this  great  enigma  of  nature,  by 
showing  that  it  is  itself  an  adaptation  and  a  means  to  an  end,  for 
the  sacrifice  of  individuals  is  the  means  for  perfecting  the  adjust- 
ments of  living  things  to  the  world  around  them  and  for  thus 
increasing  the  sum  of  life. 

The  sacrifice  of  individuals  is  the  means  by  which  variety  and 
diversity  in  living  nature,  and  the  number  of  living  beings,  are 
increased,  and,  if  life  is  adjustment,  as  I  believe  to  be  the  case, 
the  perfection  and  improvement  of  the  adjustments  of  living  beings 
is  in  itself,  and  directly,  an  addition  to  the  sum  of  life. 

"And  this,"  says  Harvey,  "is  the  round  that  makes  the  race  [of 
the  common  fowl]  eternal;  now  pullet,  now  hen,  the  series  is  con- 
tinued in  perpetuity ;  from  frail  and  perishing  individuals  an  immor- 
tal species  is  engendered.  We  therefore  see  individuals,  males  as 
well  as  females,  existing  for  the  sake  of  preparing  eggs,  that  the 
species  may  be  perennial  though  their  authors  pass  away.  And 
it  is  indeed  obvious  that  the  parents  are  no  longer  youthful,  or 
beautiful,  or  lusty,  and  fitted  to  enjoy  life,  than  while  they  possess  the 
power  of  producing  and  fecundating  eggs,  and,  by  the  medium  of 
these,  of  engendering  their  like.  But  when  they  have  accomplished 
this  grand  purpose  of  nature,  they  have  already  attained  to  the 
height  of  their  being :  the  final  end  of  their  existence  has  been 
accomplished  ;  after  this,  effete  and  useless,  they  begin  to  wither,  and 
as   if    cast    off    and  forsaken  of    nature  and  the  Deity,  they  grow 


90  THE  FOUNDATIONS   OF  ZOOLOGY 

old,  and  a-weary  of  their  lives  they  hasten  to  the  end.  How  differ- 
ent the  males  when  they  make  themselves  up  for  intercourse,  and 
swelling  with  desire  are  excited  by  the  venereal  impulse !  It  is 
surprising  to  see  with  what  passion  they  are  inflamed,  and  then  how 
pugnacious  they  prove.  But  the  grand  business  of  life  accomplished, 
how  suddenly  and  with  failing  strength,  and  pristine  fervor  quenched, 
do  they  take  in  their  swelling  sails,  and  from  late  pugnacity  grow 
timid  and  desponding.  Even  during  the  season  of  jocund  masking 
in  Venus's  domains,  male  animals  in  general  are  depressed  by  inter- 
course, and  become  submissive  and  pusillanimous,  as  if  reminded 
that  in  imparting  life  to  others  they  were  contributing  to  their  own 
destruction.  The  cock  alone,  replete  with  spirit  and  fecundity,  still 
shows  himself  alert  and  gay,  clapping  his  wings  and  crowing  tri- 
umphantly, he  sings  the  nuptial  song  at  each  of  his  espousals ;  yet 
even  he,  after  some  length  of  time  in  Venus's  service,  begins  to  fail ; 
like  the  veteran  soldier,  he  by  and  by  craves  discharge  from  active 
duty,  and  the  hen,  too,  like  the  tree  that  is  past  bearing,  becomes 
effete,  and  is  finally  exhausted." 

Usefulness  to  one's  kind  is  not  entirely  a  matter  of  physiology. 
The  wisdom  and  cunning  which  long  years  of  conflict  with  the  ways 
of  the  world  have  given  to  the  old  wolf  is  useful  to  the  pack,  even 
after  his  bodily  powers  begin  to  fail,  but  all  must  agree  with  Harvey 
that,  with  the  loss  of  all  usefulness  or  value  to  others,  the  final 
end  of  the  existence  of  the  individual,  so  far  as  this  is  recognized 
in  nature,  has  been  accomplished. 

While  the  law  that  the  adaptations  of  nature  serve  to  promote 
the  welfare  of  the  species,  rather  than  the  good  of  the  individual, 
is  as  universal  as  life,  it  is  usually  hidden  from  view  because  the 
welfare  of  the  species  is,  in  most  circumstances,  practically  the 
same  as  that  of  the  individuals  which  compose  it  in  each  genera- 
tion, and  it  is  only  when  the  two  come  into  conflict,  that  the 
law  becomes  manifest.  When  the  welfare  of  the  species  demands 
the  sacrifice  of  individuals,  the  adaptations  for  securing  this  use- 
ful end  are  as  wonderfully  perfect  and  efificient,  and  as  obvious, 
as  any  in  nature.  Most  of  them,  like  the  self-sacrificing  devotion 
of  the  maternal  instinct,  relate  to  reproduction,  and  are  so  well 
known  that  illustrations  drawn  from  other  fields  may  be  more 
novel,  and  therefore  more  impressive. 


LAMARCK  91 

The    possibility  that  the  queen  may  be  lost    exposes  a  hive  of 
bees  to  great  danger,  for  their  social  organization  requires  a  queen. 
The  danger  is  met  by  a  reserve  of  queen-larvae  ;  but  the  presence 
in  the  hive,  at  one  time,  of  a  number  of  royal  larvae  is  a  new  source 
of  danger ;  for  the   presence  of  two  reigning  queens,  at  one  time, 
when  there  is  no  need  to  send  out  a  swarm,  to  found  a  new  hive, 
would  be  demoralizing.      Queens  are  developed  from  larvae  which, 
under   ordinary   treatment,  would    have   become   workers,    and    the 
worker-bees   themselves   cause   the   selected   eggs   to    develop    into 
queens,  by  placing  them  in  large  cells  which  they  construct  for  the 
purpose  by  tearing  down  partition  walls,  and  by  feeding  the  larvae 
with  an  abundance  of  the  highly  nutritious  food  known  as  queen- 
jelly.      The   workers   tend   the    royal    larvae    with    unceasing   care, 
until  they  are    nearly  ready  to   escape,  when  they  gnaw  away  the 
wax  until  it  becomes  transparent  and  so  thin  as  to  permit  ventila- 
tion ;    but   if    the   queen-mother   be    still   in   the    hive   waiting   for 
favorable  weather  to  lead  forth  a  swarm,  the  young  queen  is  not 
permitted   to    leave   her   cell.      The  royal  guard  of  workers  is  re- 
enforced,  and   the    cell   is   thickened   by   new   layers   of   wax,  per- 
forated by  a  small  opening,  through  which  the  prisoner  thrusts  her 
tongue,  in   order   that   her   attendants  may  feed  her ;    for   the    old 
queen    is   impelled    by  an    implacable    instinct    to    destroy  all    the 
young   queens    she    can    reach.       For   this  reason  the  workers  use 
every  means  to   keep    her   away  from   the   royal    cells    so  long  as 
there  is  a  prospect  of   swarming.     They  guard  every  approach  to 
the  cell,  and  even,  forgetting  their  allegiance,  bite  and   strike  and 
push  her,  and  beat  her  off  whenever  she  tries  to  approach.     When 
the  old  queen  has  left  the  hive  with  a  swarm,  and  one  of  the  young 
queens  is  permitted  to  escape  and  take  her  place,  she  at  once  seeks 
to  destroy  her  sisters,  but  is  bitten,  pulled,  and  shoved  without  cere- 
mony until  she  is  driven  off.     As  the  season  advances,  until  it  be- 
comes too  late  for  swarming,  the  impulses  of  the  workers  change 
completely.     They  cease  to  resist  her,  and  even  incite  her  to  destroy 
her  rivals.     She  now  attacks  the  royal  brood,  and  stings  them  to  death, 
one  after  another,  in  their  cells,  while  the  workers,  who  are  spectators 
of  the  carnage,  share  in  the  spoil,  greedily  devouring  any  food  they 
may  find  in  the  cells,  and  even  sucking  the  fluids  from  the  carcasses 
before  they  toss  them  out  of  the  cells  and  drag  them  away. 


92  THE  FOUNDATIONS  OF  ZOOLOGY 

Few  things  in  nature  are  more  wonderful  than  the  perfection 
of  the  organization,  in  the  hive,  for  ensuring  the  presence  of  one 
queen,  and  for  destroying  all  the  others ;  but  the  provision  the 
royal  larva  makes  for  its  own  murder  seems  to  claim  a  place 
among  these  few. 

When  a  larval  bee  has  completed  its  growth,  and  is  about  to 
assume  the  pupa-state,  from  which  it  is  to  emerge  as  a  perfect 
bee,  it  spins,  like  the  larvae  of  many  other  insects,  a  protective 
cocoon  of  silk,  around  its  body,  but,  as  this  is  firm  enough  to 
offer  some  resistance  to  a  sting,  and  as  it  might  even  injure  the 
murderess,  the  royal  larva  spins  an  imperfect  cocoon,  open  behind, 
and  covering  only  the  head,  thorax,  and  first  abdominal  ring. 
Huber,  who  discovered  this  peculiarity,  pointed  out  that  the  pur- 
pose of  the  imperfection  is  to  expose  the  soft  abdomen  of  the 
royal  larva  naked  to  the  mortal  sting  of  the  reigning  queen. 

The  supreme  importance  of  the  species,  and  the  relative  insig- 
nificance of  the  individual,  are  well  illustrated  by  animals  which 
have  dropped  their  adult  structure  out  of  their  life  history,  that  the 
perpetuation  of  the  species  may  be  the  more  assured.  The  flying 
butterfly,  with  its  highly  perfected  sense-organs,  leads  an  active, 
independent  life,  which  must,  according  to  any  standard,  be  held 
higher  than  the  helpless  creeping  life  of  the  blind  caterpillar,  yet 
many  species  of  butterflies  and  moths  have  lost  this  most  perfect 
stage  in  their  life  so  that  they  cannot  wander  away  from  the 
plants  which  are  best  suited  for  their  larvae,  or  lay  their  eggs  in 
any  but  the  best  spot.  The  active,  swimming  jelly-fish,  with  its 
complicated  muscular  apparatus,  its  centralized  nerve-ring,  and  its 
well-developed  organs  of  special  sense,  is  a  higher  organism  than 
the  sessile  plant-like  hydroid ;  yet  many  hydroids  which  live  in 
places  where  swimming  adults  might  be  swept  out  into  the  open 
ocean  far  away  from  any  resting-place  for  the  larvae,  have  gradually 
lost  the  jelly-fish  stage,  and  they  now  pass  their  lives  and  repro- 
duce their  kind,  in  what  was,  at  one  time,  their  larval  or  immature 
condition.  From  the  standpoint  of  the  individual,  the  degeneration 
of  the  jelly-fish  into  a  sexual  larva  is  distinctly  a  step  backwards, 
marked  by  disregard  of  all  the  best  results  of  a  long  history  of 
gradual  progress  and  improvement.  It  is  a  sacrifice  of  all  that  is 
"best"  in  the  life  of  the  individual  for  the  good  of  the  species. 


LAMARCK  93 

Many  other  groups  of  animals,  notably  the  Crustacea  and  in- 
sects, furnish  familiar  examples  of  the  loss  of  the  adult  structure, 
and  of  the  broader  life  which  it  permitted,  in  order  that  the  per- 
petuation of  the  species  may  be  the  more  assured.  They  illus- 
trate, in  the  clearest  way,  the  supreme  importance  of  the  species, 
and  the  "indifference"  of  nature  to  the  welfare  of  the  individual 
when  this  welfare  is  incompatible  with  the  good  of  the  species  as 
a  whole.  Whether  we  agree  with  Weismann  that  old  age  and 
natural  death  owe  their  existence  to  their  usefulness  or  not,  they 
are  clearly  useful  to  the  species,  but  it  is  not  necessary  to  dwell 
upon  the  subject,  for  the  examples  which  we  have  considered  are 
enough  to  illustrate  the  familiar  fact  that  the  end  which  the 
adjustments  of  living  things  bring  about  is  the  good  of  the  species, 
rather  than  the  success  of  individuals. 

All  the  adaptations  of  living  nature  are  like  the  bee's  sting 
and  the  poison  of  serpents,  inasmuch  as  their  use  is  exhibited  in 
the  lives  of  other  individuals  than  those  which  exhibit  the  struct- 
ural adjustment.  It  also  seems  clear  that,  even  if  the  direct 
effects  of  nurture  are  both  beneficial  and  inherited,  they  can  have 
no  controlling  or  notable  influence  in  the  production  of  the  sort 
of  adjustments  which  actually  exist,  however  competent  they  may 
be  to  produce  others.  Can  any  zoologist  say,  with  Lysicles: 
"  Look  throughout  the  universe,  and  you  shall  find  birds  and 
fishes,  beasts  and  insects,  all  kinds  of  animals,  with  which  creation 
swarms,  constantly  engaged  by  instinct  in  the  pursuit  of  sensible 
pleasure ;  and  shall  man  alone  be  the  grave  fool,  who  thwarts  and 
crosses  and  subdues  his  appetites,  while  his  fellow-creatures  do  all 
most  joyfully  and  freely  indulge  them.?" 

Must  he  not  rather,  with  Euphranor,  "  infer  the  excellency  of 
animal  bodies  from  observing  the  frame  and  fitness  of  their  sev- 
eral parts,  by  which  they  mutually  conspire  to  the  well-being  of 
each  other  as  well  as  of  the  whole  "  .-' 

Certain  Neo-Lamarckians  assert,  however,  that  while  natural 
selection  is  the  chief  factor  in  the  origin  of  species,  it  cannot  act 
unless  the  conditions  of  life  furnish  the  necessary  "variations." 
I  shall  examine  this  proposition  in  another  place,  and  shall  now 
do  no  more  than  to  point  out  that,  unless  the  difl['erences  between 
individuals  which  are  brought  about  by  nurture  are  useful,  prior  to 


94  THE  FOUNDATIONS  OF  ZOOLOGY 

selection,  they  are  fortuitous,  so  far  as  their  fitness  is  in  question. 
The  mere  fact  that  species  change  is  no  more  remarkable  than  the 
change  of  seasons,  or  the  melting  of  a  snowdrift ;  nor  do  I  suppose 
that  any  one  believes  that  any  change  ever  takes  place  in  nature 
without  those  antecdent  changes  which  we  call  physical  causes. 
The  thing  to  be  explained  is  not  that  species  change,  but  how  the 
changes  of  species  tend  to  establish  harmony  between  them  and 
the  world  in  which  they  live.  Since  many  species,  many  more  in 
fact  than  all  that  now  exist,  have  disappeared  during  the  long 
history  of  life  without  leaving  descendants ;  and  since  the  early 
extinction  of  the  blood  of  the  vast  majority  of  the  individual 
organisms  which  now  exist  can  be  demonstrated,  the  adjustments 
of  these  which  survive  cannot  be  accounted  for  by  any  law  of 
"  necessary  "  or  "  universal  "  progress  or  evolution. 

Living  things,  like  everything  else,  act  in  accordance  with  the 
laws  of  matter  and  motion.  Animals,  like  clouds,  grow  lighter  as 
they  ascend  a  mountain,  and  their  volume  increases  as  their 
temperature  rises ;  but  changes  of  this  sort  are  all  that  external 
changes  can  produce  prior  to  selection,  unless  they  tend  to  bring 
about  responsive  modification,  or  adjustr^ent;  and  it  is  begging  the 
question  to  attribute  the  origin  of  this  tendency  to  the  inheritance 
of  modifications  in  the  right  direction  unless  some  reason  why  the 
right  ones  should   be   the  ones  which  are  inherited  is  pointed  out. 

I  have  tried  to  show,  page  66,  that  instead  of  a  preliminary 
condition  to  selection,  the  adaptive  influence  of  the  environment, 
so  far  as  this  influence  is  adaptive,  is  the  result  of  past  selection, 
and  Darwin's  explanation  of  the  origin  of  species  by  selection  is 
the  only  one  worth  considering. 

It  scarcely  seems  necessary,  at  this  late  day,  to  point  out  that 
by  foytnitons  variations,  Darwin  means  those  differences  between 
individuals  which  stand  in  no  discoverable  relation  to  the  use  to 
which  they  are  turned  by  selection ;  for  Darwin  admits,  as  every 
one  must,  that  if  there  were  no  changes  in  the  external  world  we 
should  have  no  reason  to  expect  any  difference  between  individual 
living  things;  but,  whatever  may  be  our  opinion  of  the  nature  of 
those  "variations"  which  are  said  to  be  a  necessary  preliminary  to 
selection,  it  seems  clear  that  the  effects  of  the  conditions  of  life 
cannot  be  transmitted  to  future  generations,  unless   the  organisms 


LAMARCK  95 

which  are  exposed  to  these  conditions  have  children.  If  sterile 
organisms,  which  have  no  descendants,  are  ever  gradually  adapted 
to  the  conditions  of  their  life,  the  mechanical  effect  of  these  con- 
ditions can  have  no  part,  direct  or  indirect,  incipient  or  otherwise, 
in  the  production  of  the  adjustment.  As  the  sterile  workers  of 
allied  species  of  social  insects  differ  from  each  other  in  habits,  in 
instincts,  and  in  anatomical  structure,  more  than  the  males  and 
the  fertile  females,  this  diversity  among  the  workers  must  have 
become  established  after  the  workers  themselves  had  become 
sterile. 

Whole  books  have  been  written  on  the  marvellous  fitness  of 
the  structure,  the  instincts,  and  the  habits  of  the  worker  of  the 
honey-bee  for  its  life  of  active  industry,  a  life  in  which  the  male 
has  no  share,  and  from  which  the  female  is  cut  off  by  her  seclu- 
sion in  the  depths  of  the  hive,  and  by  her  devotion  to  her  own 
peculiar  duties.  While  the  queen  and  the  drones  are  well  fitted 
for  their  own  parts  in  the  social  organization  of  the  hive,  these 
duties  are  quite  simple,  and  very  different  from  the  duties  of  the 
workers ;  and  as  these  latter  do  not  normally  have  descendants, 
and  as  they  never,  under  any  circumstances,  have  female  descen- 
dants, all  the  workers  are  the  descendants  of  queens  and  not  of 
workers. 

Their  wonderful  and  admirable  fitness  for  their  own  most  neces- 
sary part  in  the  economy  of  the  hive  must,  therefore,  be  inherited 
from  parents  who  have  never  been  exposed  to  those  conditions  to 
which  the  workers  are  adapted ;  and  this  adaptation  cannot  be 
due  to  the  inheritance  of  the  effect  of  these  conditions ;  nor  can 
we  believe  that  they  are  inherited  from  some  remote  time,  when 
the  workers  were  perfect  females,  or  when  the  queens  were  also 
workers;  for  the  sterile  workers  of  allied  species  differ  among 
themselves,  thus  proving  that  they  have  undergone  modification 
since  they  became  sterile. 

Here  we  have  a  most  complicated  and  perfect  adjustment,  of 
marvellous  efficacy,  to  external  conditions  which  are  of  such  a 
character  as  to  prove  that  the  inheritance  of  the  effect  of  these 
conditions  has  had  no  part  in  the  production  of  the  adaptation. 

This  is  not  a  solitary  case,  but  a  familiar  illustration  of  a 
general   law ;    for    a    little    thought    will    show    that    most    of    the 


96  THE  FOUNDATIONS  OF  ZOOLOGY 

adaptations  of  living  nature  have  much  in  common  with  those 
which  are  presented  by  a  hive  of  bees. 

Some  of  the  members  of  the  floating  community  known  as  a 
siphonophore  have  mouths  and  stomachs  which  furnish  an 
abundant  supply  of  food  for  all ;  and  this  food  flows  through 
tubes  to  the  places  where  it  is  needed,  as  water  flows  to  all  the 
houses  in  a  city.  Other  members  of  the  community  do  the 
swimming  for  the  whole,  and  are  especially  fitted  for  this  work, 
which  calls  for  an  abundant  supply  of  food  to  replenish  the 
energy  expended  in  swimming.  As  they  have  no  mouths  they 
take  no  food  for  themselves,  but  their  bodies  are  supplied  with 
branches  from  the  main  canal,  distributed,  like  blood-vessels,  in 
the  course  of  the  muscles.  Other  mouthless  members  are  con- 
verted into  protecting  lids,  and  others  into  long  poisonous  arms  for 
destroying  the  prey  or  for  repelling  enemies.  Others  form  floats 
from  which  the  whole  hangs  suspended  in  the  water,  while  still 
others  are  sexual,  male  or  female,  and  carry  on  the  work  of 
reproduction. 

A  colony  of  siphonophores  is  both  a  community  and  a  unit ; 
for  while  the  members  are,  to  a  certain  degree,  independent,  they 
all  work  together  for  the  common  good,  and  find  all  the  condi- 
tions for  perfect  life  nowhere  but  in  the  community.  A  hive  of 
bees  is,  also,  a  unit ;  for  while  each  bee  is  able  to  live  an  in- 
dependent life,  the  welfare  of  all  depends  upon  the  integrity  of 
the  community,  although  there  is  no  physical  continuity  between 
its  members,  as  there  is  in  a  siphonophore.  A  hive  of  bees  has 
been  called  a  "  state "  to  distinguish  it  from  communities  like  the 
siphonophore,  in  which  the  bond  of  union  between  the  members 
is  organic.  As  all  the  members  of  the  siphonophore-community 
are  physically  bound  together  by  structural  continuity,  into  an  or- 
ganic unit,  it  is  not  possible  to  prove  that  some  influence  does  not 
pass  from  the  bodies  of  those  which  are  specialized  for  the  capture 
or  the  digestion  of  food,  or  from  the  bodies  of  these  which  are 
specialized  for  swimming,  to  the  germ-cells  in  the  bodies  of 
those  which  are  specialized  for  reproduction ;  but  the  history  of 
the  sterile  workers  among  the  bees  shows  that  there  is  no  need 
for  imagining  the  transmission  of  any  such  influence,  for  there  is 
no  organic  connection  between  the  bodies  of  the  workers  and  the 


LAMARCK.  97 

germ-cells  in  the  bodies  of  the  queen  or  of  the  drones,  and,  therefore, 
no  channel  through  which  such  an  influence  can  be  propagated. 

I  hope  to  show,  in  another  place,  that  natural  selection  meets 
all  the  difficulties  we  find  in  the  hive  of  bees.  If  so,  it  must  also 
be  an  adequate  explanation  of  the  origin  of  the  siphonophore  as 
well;  and  the  hypothesis  that  the  germ-cells  are  affected  by  the 
conditions  of  the  life  of  the  sterile  members  of  the  community  is 
as  superfluous  in  the  latter  case  as  it  is  inadmissible  in  the  case  of 
the  bee. 

While  the  siphonophore  has,  on  the  one  hand,  many  features  of 
resemblance  to  a  hive  of  bees,  it  also,  on  the  other  hand,  resembles 
the  body  of  an  ordinary  animal,  for  this  is,  also,  both  an  unit  and 
a  community.  The  cells  which  compose  it  have  a  certain  individ- 
uality, and  are  specialized  for  different  functions,  as  are  the  bees 
and  the  members  of  the  hydroid  community.  Certain  cells  are  set 
apart,  very  early  in  the  history  of  the  whole,  in  mammals  long 
before  birth,  as  germ-cells,  destined  to  become,  in  time,  the  ova  or 
the  spermatoa  of  the  adult,  while  all  the  other  specialized  cells  are 
out  of  the  line  of  descent  to  future  generations,  like  the  worker- 
bee.  The  constituent  cells  of  the  body  are  much  more  intimately 
bound  together,  and  are  much  more  dependent  for  their  welfare 
upon  the  integrity  of  the  whole,  than  the  bees  in  the  hive,  or  the 
members  of  the  siphonophore,  and  we  cannot  prove  that  they  are  not 
all  in  some  sort  of  telegraphic  or  sympathetic  connection  with  the 
germ-cells;  in  fact,  there  are  reasons  for  believing  that  a  connection 
of  this  sort  does  actually  exist;  but  it  is  no  more  necessary  to  call 
in  its  aid  to  account  for  the  origin  of  a  cellular  community,  like  the 
body  of  a  dog,  than  it  is  to  imagine  anything  of  this  sort  to  account 
for  the  origin  of  the  worker-bees;  and,  in  this  case,  the  facts  must 
be  accounted  for  without  this  hypothesis  or  not  at  all. 

Even  if  it  should  be  proved,  as  seems  not  improbable,  that  the 
germ-cells  are  in  some  sort  of  responsive  connection  with  all  the 
other  elements  of  the  body,  it  would  still  remain  true  that  the  adjust- 
ments which  we  find  in  living  things  are  of  such  a  character  as 
to  prove  that  the  "inheritance  of  acquired  characters"  has  had  no 
controlling  influence  in  their  production. 

Some  may  ask  whether  it  may  not  be  possible  that,  while  natural 
selection  is  the  thief  factor  in  the  origin  of  species,  there  may  still 

H 


98  THE  FOUNDATIONS   OF  ZOOLOGY 

be  a  residuum  to  be  accounted  for  by  the  "  inheritance  of  acquired 
characters."  For  all  I  know  this  may  be  not  only  possible,  but 
actually  the  case.  I  have  never  felt  the  slightest  interest  in  a  priori 
demonstrations  of  the  impossibility  of  this  sort  of  inheritance,  and, 
for  all  I  know  to  the  contrary,  proof  of  its  occurrence  may  be  found 
at  any  time,  although  I  know  no  good  evidence  of  its  occurrence. 
I  had  satisfied  myself,  long  before  the  recent  revival  of  interest  in 
the  matter,  that  whether  it  be  a  real  factor  or  not,  the  so-called 
Lamarckian  factor  has  little  value  as  a  contribution  to  the  solution 
of  the  problem  of  the  origin  of  species;  and  renewed  study  has 
strengthened  this  conviction. 


LECTURE   V 

MIGRATION    IN    ITS   BEARING   ON    LAMARCKISM 


LECTURE   yi 

MIGRATION   IN   ITS   BEARING   ON   LAMARCKISM 

In  the  last  lecture  I  tried  to  show  that  the  adaptations  of 
nature  are  primarily  for  the  good  of  the  species ;  that  they  are 
beneficial  to  individuals  only  so  far  as  these  individuals  are  essen- 
tial to  the  welfare  of  the  species ;  and  that  they  often  are  inju- 
rious or  destructive  to  the  individual.  I  also  pointed  out  that, 
since  this  is  so,  the  nurture  of  the  individual  does  not  seem  to 
have  any  bearing  upon  the  origin  of  adaptation. 

To  my  mind,  no  illustration  of  this  great  natural  law  is  more 
simple  or  more  easy  to  understand,  than  that  afforded  by  some  of 
the  phenomena  of  migration. 

The  young  salmon  which  is  born  in  a  mountain  stream  is 
soon  impelled,  by  something  in  its  nature,  to  journey  downward, 
often  many  hundred  miles,  until  it  reaches  the  unknown  ocean, 
where  it  would  discover,  if  it  had  faculties  for  anything  so  sub- 
jective as  discovery,  that,  while  it  was  born  in  a  mountain  stream, 
it  was  made  for  life  in  the  great  ocean. 

•It  has  brought  from  its  mountain  home  a  natural  aptitude  for 
eluding  .all  the  strange  enemies,  and  for  avoiding  all  the  novel 
dangers,  which  it  finds  in  this  new  world ;  and  it  leads  an  active 
predatory  life,  fiercely  pursuing  and  destroying  its  natural,  but 
previously  unknown,  prey ;  growing  rapidly  ;  quickly  acquiring  all 
the  characteristics  of  the  adult  salmon ;  and  storing  up  the  intense 
nervous  energy,  and  the  muscular  strength,  which  will  be  needed 
for  forcing  its  way  up  the  rapids  in  the  mountain  torrents,  leap- 
ing waterfalls,  and  fighting  for  its  passage,  where  it  had,  long 
ago,  darted  down  with  the  current.  As  sexual  maturity  ap- 
proaches, some  stimulus,  which    has    its    origin    in    the    developing 

1  Reprinted  with  slight  changes  from  the  Popular  Science  Monthly.     April,  1898. 

lOI 


I02  THE  FOUNDATIONS  OF  ZOOLOGY 

reproductive  organs,  impels  it  to  leave  the  ocean,  and,  entering 
the  mouth  of  a  river,  to  journey  on  and  on,  often  a  thousand  miles 
or  more,  to  its  sources  in  the  mountains. 

At  this  time  the  king  of  fishes,  as  it  is  well  called,  is  in  physi- 
cal perfection,  with  few  rivals  in  beauty,  or  strength,  or  fierce 
energy,  or  indomitable  courage  and  perseverance ;  but  its  strength 
is  soon  exhausted  in  surmounting  the  obstacles,  and  in  fighting 
the  rivals,  which  oppose  its  progress ;  until,  at  last,  worn  and  thin, 
torn  and  mangled  by  battle,  and  battered  by  rocks  and  whirl- 
pools, with  its  skin  in  rags,  its  fins  crippled  and  bleeding,  and  its 
whole  body  from  nose  to  tail  bruised  and  emaciated,  nothing  of 
its  kingly  nature  remains  except  the  indomitable  impulse,  which 
nothing  can  quench,  still  urging  it  onwards,  until,  if  any  life 
remain,  it  at  last  reaches  the  breeding  ground. 

One  of  the  most  magnificent  species  of  this  kingly  genus  was 
so  abundant  in  the  Columbia  River,  before  canning  houses  had 
reduced  its  numbers,  that  the  lower  reaches  were  packed  with 
salmon,  while  the  surface  was  covered  with  the  drifting  bodies 
of  those  which  had  perished  in  fierce  struggles  with  the  crowd: 
yet  there  is  good  authority  for  the  assertion  that  not  a  single  one 
ever  returns  alive  from  the  breeding  grounds  in  the  head-waters 
of  the  St.  Cloud.  The  whole  race  is  wiped  out,  utterly  exter- 
minated, as  soon  as  it  arrives  at  maturity  and  physical  perfec- 
tion, in  order  that  the  perpetuation  of  the  species  may  be  assured. 
The  whole  object  and  end  of  the  beautifully  coordinated  body, 
which  is  provided  for  by  such  admirable  and  wonderful  adapta- 
tions, which  is  built  up  so  slowly  and  at  so  much  cost,  is  rapid 
and  total  destruction. 

The  marvellous  instinct  which  leads  the  young  fish  to  the 
ocean ;  the  organization  and  the  habits  which  fit  it  for  marine 
life  —  all,  in  a  word,  which  makes  of  the  salmon  our  ideal  of  a 
lordly  fish  —  is  worth  nothing  as  compared  with  the  welfare  of 
generations  yet  unborn. 

Scientific  men  who  are  not  zoologists  are  fond  of  telling  us 
science  has  nothing  to  do  with  the  Why }  and  is  concerned 
only  with  the  How.?  but,  in  zoology,  it  is  often  easy  to  discover 
why  an  action  is  performed,  while  we  are  very  ignorant  of  the 
structural    conditions  under  which  it  takes  place.     As  all  the  indi- 


Mf ORATION  IN  ITS  BEARING   ON  LAMARCKISM  103 

vidual  California  salmon  seem  to  act  alike,  and  as  the  young 
salmon  has  no  opportunity  for  parental  instruction,  it  seems 
probable  that  everything  it  does  is  the  result  of  its  structure, 
or  of  such  nurture  as  this  structure  provides  for ;  but  we  can 
safely  say  that  no  one  now  living  is  at  all  likely  to  discover  or 
to  predict  its  migration  from  the  study  of  its  body,  although  the 
reason  why  the  migration  takes  place  is  obvious. 

Whole  books,  and  not  a  few  of  them,  have  been  devoted  to 
learned  speculations  on  the  nature  of  the  impulse  which  leads  to 
the  migration  of  birds,  and,  while  the  subject  is  most  fascinating, 
the  value  of  the  result  has  not,  in  all  cases,  been  commensurate 
with  the  labor. 

Newton  "  Encyclopaedia  Britannica,"  article  Birds  says :  "  We 
have  here  more  than  enough  to  excite  our  wonder,  and  indeed 
are  brought  face  to  face  with  perhaps  the  greatest  mystery  which 
the  whole  animal  kingdom  presents,  —  a  mystery  which  attracted 
the  attention  of  the  earliest  writers,  and  can  in  its  chief  point  be 
no  more  explained  by  the  modern  man  of  science  than  by  the 
simple  minded  savage  or  the  poet  or  prophet  of  antiquity.  Some 
facts  are  almost  universally  known  and  have  been  the  theme  of 
comment  in  all  ages  and  in  all  lands.  The  hawk  that  stretches 
her  wings  toward  the  south  is  as  familiar  to  the  latest  Nile-boat 
traveller  or  dweller  on  the  Bosphorus,  as  of  old  to  the  author  of 
the  Book  of  Job. 

"The  autumnal  thronging  of  myriads  of  water-fowl  by  the 
rivers  of  Asia  is  witnessed  by  the  modern  sportsman,  as  it  was  of 
old  by  Homer.  Anacreon  welcomed  the  returning  swallow,  in  num- 
bers which  his  imitators  of  the  colder  north,  to  whom  the  associa- 
tions connected  with  it  are  doubly  strong,  have  tried  in  vain  to 
excel.  The  Indian  of  the  fur-countries,  in  forming  his  rude 
calendar,  names  the  recurring  moons  after  the  birds  of  passage 
whose  arrival  is  coincident  with  their  changes.  But  there  is  no 
need  to  multiply  instances.  The  flow  and  ebb  of  the  mighty 
feathered  wave  has  been  sung  by  poets  and  reasoned  by  philoso- 
phers, has  given  rise  to  proverbs,  and  entered  into  popular 
superstitions,  and  yet  we  may  say  of  it  still  that  our  ignorance  is 
immense." 

While  this  author  does  not  exaggerate  either  the  interest  or  our 


I04  THE  FOUNDATIONS  OF  ZOOLOGY 

ignorance  of  the  life  of  birds,  which  goes  on  in  regions  which 
are  almost  inaccessible  and  unknown  to  us,  there  is  no  reason 
to  suppose  their  migrations  are  any  more  mysterious  than  most 
biological  problems ;  for  it  is  doubtful  whether  the  modern  man  of 
science  is  much  more  able  than  the  simple-minded  savage  or  the 
poet  and  prophet  to  tell  how  all  the  coordinated  faculties  of  a 
predaceous  animal  are  so  thrown  into  action  by  the  stimulus  of 
hunger  as  to  lead  to  the  pursuit  and  capture  of  prey;  yet  there 
is  no  mystery  in  the  physiology  of  hunger,  for  while  there  is 
much  we  do  not  understand,  we  do  know  that  hunger  incites  to 
actions   which   are  responsive,  and  adapted  for  satisfying  hunger. 

So  also  we  may  make  progress  in  our  study  of  migration  not- 
withstanding ignorance  of  the  nature  of  the  impulse  which  excites 
and  regulates  it.  While  I  gratefully  acknowledge  my  debt  to 
Newton  for  many  of  the  facts  in  this  chapter,  I  am  not  able  to 
agree  with  him  that  there  is  any  peculiar  mystery  in  the  subject. 

While  there  is  reason  to  believe  almost  every  bird  of  temperate 
and  arctic  climates  is  migratory  to  some  degree,  those  which 
simply  range  over  a  wider  area  at  one  season  than  at  another 
present  nothing  notable,  and  it  is  only  in  regions  which  are  al- 
most or  quite  abandoned  by  birds  for  part  of  the  year  that  their 
migrations  attract  the  attention  of  students.  As  many  birds  which 
are  most  valued  as  food  are  found  in  temperate  regions  for  only 
a  short  time  in  spring  and  fall,  sportsmen  and  hunters  and  all 
who  pursue  them  for  food  have  been  familiar  with  the  habits  of 
the  birds  of  passage  from  the  dawn  of  history ;  but  most  of  the 
best  literature  on  the  subject  is  by  northern  ornithologists,  and 
the  home  of  the  writer  has  had  and  still  has  great  influence  upon 
opinion  as  to  the  meaning  and  origin  of  the  migratory  habit. 

Scandinavians,  and  Saxons,  and  Anglo-Saxons  are  home-loving 
folks  who,  in  all  their  wanderings  through  this  world  of  care, 
keep  a  warm  affection  for  the  fatherland,  and  are  much  given  to 
the   belief  that  their  home  is  the  choicest  spot  on  earth. 

A  learned  professor  in  the  University  of  Upsala  once  wrote  a 
book  to  prove  that  the  Garden  of  Eden  was  in  Sweden,  by  the 
simple  and  obvious  argument  that  no  one  who  knows  the  delights 
of  life  in  that  country  can  believe  Paradise  was  anywhere  else. 
He  showed  that  the  Atlantis  of  Plato,  the  country  of  the   Hyper 


MIGRATION  IN  ITS  BEARING   ON  LAMARCKISM  105 

boreans,  the  garden  of  the  Hesperides,  the  Fortunate  Islands,  and 
the  Elysian  Fields  are  but  faint  and  imperfect  reminiscences  of 
the  lovely  and  favored  climes  of  Sweden,  from  which  the  Greeks 
themselves  derived  their  alphabet,  their  astronomy,  and  their  religion. 

To  the  men  of  the  north  home  seems  the  natural  refuge  of  the 
birds,  and,  as  much  of  the  literature  of  migration  is  northern, 
the  birthplace  of  summer  birds  has  been  regarded  as  their  true 
or  natural  home,  and  while  their  disappearance  in  winter  has 
seemed  to  call  for  explanation,  their  return  in  summer  has  been 
regarded  as  a  matter  of  course,  for  the  intense  love  of  home 
which  many  exhibit  has  seemed  enough  to  draw  them  back  when 
the  season  of  scarcity  is  over. 

It  is  the  "  homing  "  instinct  which  makes  the  carrier  pigeon  so 
useful  to  man ;  and  one  of  the  most  impressive  features  of  the 
migratory  habit  is  the  definiteness  of  the  journey  northwards, 
which  often  leads  to  a  particular  bush  or  ledge  of  rocks.  Many 
species  of  our  common  birds  lay  their  eggs  year  after  year  in  the 
same  nest,  although  they  may  spend  the  rest  of  the  year  in  the 
heart  of  a  strange  country  thousands  of  miles  away,  and  although 
the  chosen  spot  may  have  changed  so  much  that  it  is  no  longer 
a  judicious  selection. 

A  bottle  in  the  branches  of  a  tree  at  Oxbridge  in  England  is 
known  to  have  been  occupied  every  year,  with  only  one  exception, 
since  1785,  by  a  pair  of  blue  titmice;  and  on  a  hill  in  Finland, 
well  known  to  tourists  as  the  most  southern  point  in  Europe 
where  the  sun  may  be  seen  at  midnight,  a  nest  is  said  to  have 
been  occupied  by  a  pair  of  peregrine  falcons  ever  since  the  visit 
of  the  French  astronomer  Maupertius  in  1736.  There  are  other 
records  of  similar  instances,  and  while  it  is  not  probable  that  the 
birds  which  visit  a  nest  year  after  year  for  centuries  are  the  same, 
the  fact  is  all  the  more  remarkable  if  they  belong  to  successive 
generations.. 

According  to  folklore  some  of  the  summer  birds  do  not  go 
away,  but  hide  near  home,  and  Cams,  in  his  history  of  zoology, 
refers  to  several  learned  writers  who,  early  in  the  seventeenth 
century,  quoted  from  the  older  literature  much  venerable  authority 
for  the  belief  that  the  swallows  hide  through  the  winter  in  holes 
and  clefts  in  the  rocks,  or  even  under  the  water. 


I06  THE  FOUNDATION'S   OF  ZOOLOGY 

Many  writers  on  migration  believe,  as  they  have  been  told 
from  childhood,  that  the  birds  go  south  to  escape  the  rigors  of  a 
northern  winter,  although  little  reflection  is  needed  to  show  that 
no  animals  are  more  thoroughly  protected  or  more  indifferent  to 
changes  of  temperature,  and  that,  while  sea-birds  are  highly  mi- 
gratory, the  open  waters  of  arctic  seas  are  little  colder  in  winter 
than  in  summer.  Nestlings  are  often  killed  by  cold,  and  eggs 
require  a  high  temperature,  but  old  birds  are,  as  a  rule,  very 
indifferent  to  cold. 

When  this  fact  is  recognized,  the  prevailing  belief  is  that  birds 
leave  their  homes  in  search  of  food,  and  scarcity  is  most  certainly 
an  important  factor  in  the  origin  of  migration,  but  this  view  of 
the  matter  fails  to  show  why,  with  the  whole  world  to  choose  from, 
they  do  not  settle  in  lands  which  are  habitable  the  year  round. 

"  The  shuddering  tenant  of  the  frigid  zone 
Boldly  proclaims  that  happiest  spot  his  own  " ; 

and  to  the  Esquimaux  the  return  of  the  birds  seems  only  natural ; 
but  to  us,  who  are  not  Esquimaux,  the  wonder  is  not  that  any- 
thing which  can  get  away  should  do  so,  but  why  the  birds  pass 
by  so  many  lovely  and  fertile  regions  to  seek  a  home  in  the  bar- 
ren and  desolate  ends  of  the  earth ;  and  it  is  plain  that,  of  the 
two  journeys,  which  make  up  the  migration,  the  spring  and  sum- 
mer visit  to  northern  lands  and  waters  is  at  least  as  remarkable, 
and  as  well  worthy  of  consideration,  as  the  journey  southwards  in 
the  fall. 

Failure  of  food  in  the  birthplace  is  no  doubt  the  chief  reason 
why  the  migratory  birds  do  not  spend  the  whole  year  there,  and, 
so  far,  is  a  sufficient  reason  for  migration,  for  no  animals  are 
better  fitted  for  moving  from  regions  of  scarcity  to  regions  of 
abundance,  but  they  are  little  more  able  than  creeping  things  to 
establish  themselves  in  new  lands  which  are  already  well  stocked 
with  inhabitants,  and,  like  other  animals,  they  are  kept  within  the 
limits  of  their  natural  habitat  by  competitors  and  enemies,  rather 
than  by  physical  barriers,  although  their  power  to  wander  and  to 
overcome  physical  barriers  is  without  a  parallel,  for  there  are  few 
oceanic  islands,  however  remote,  which  are  not   inhabited  by  land 


MIGRATION  IN  ITS  BEARING   ON  LAMARCKISM  10/ 

birds,  descended  from  lost  wanderers  who,  finding  these  spots 
unoccupied,  have  been  able  to  establish  themselves. 

The  list  of  North  American  birds  which  are  occasionally  found 
in  Europe  is  a  long  one,  and  stray  .specimens  of  the  gray  plover, 
whose  summer  home  is  the  shore  of  the  Arctic  Ocean,  have  been 
found  at  the  Cape  of  Good  Hope,  in  Ceylon,  in  Australia,  in  New 
Zealand,  and  in  Tasmania.  Most  of  the  wanderers  are  shore  birds 
which  make  long  migrations  and,  being  much  exposed  to  storms, 
are  often  driven  far  out  of  their  path,  but  this  is  not  always  the 
case,  for  the  great  albatross  follows  ships  across  the  whole  breadth 
of  the  South  Pacific,  or  nearly  half  the  circumference  of  the 
earth.  Many  birds  seem  to  make  their  whole  journey  by  a  single 
flight,  for  some  which  are  common  in  the  West  Indies  and  in 
Nova  Scotia  are  almost  unknown  within  the  limits  of  the  United 
States,  making  the  whole  journey  past  our  borders  by  water  and 
probably  by  a  single  flight.  The  blue-throat,  which  breeds  in  the 
northern  part  of  Scandinavia,  is  so  seldom  found  in  Europe  south 
of  the  Baltic  that  there  seems  to  be  good  evidence  that  it  makes 
its  whole  journey  to  its  winter  quarters,  which  are  in  the  region 
of  the  upper  Nile,  by  a  single  flight. 

There  is  no  reason  to  suppose  that  all  migratory  birds  inherit 
the  habit  from  a  common  source,  or  that  its  purpose  is  always 
the  same ;  and  many  birds  of  prey  seem  to  have  acquired  the 
habit  of  ranging  far  in  winter  in  search  of  food,  and  of  following 
their  prey  into  warmer  regions,  to  return  to  their  birthplace  in 
seasons  of  reproduction.  In  these  cases  the  birthplace  may  have 
been  the  original  home,  before  the  migratory  habit  was  acquired, 
and  the  scarcity  of  food  the  reason  why  it  was  acquired ;  and  the 
influence  of  scarcity  in  causing  migration  is  well  shown  by  the 
occasional  migrations  of  certain  prolific  animals  which  do  not 
ordinarily  leave  their  birthplaces,  although,  when  these  become 
overstocked,  migrations  take  place,  just  as  colonies  are  sent  out 
by  the  people  of  thickly  settled  countries  to  find  new  room  for 
growth  in  foreign  lands.  From  time  to  time,  at  irregular  inter- 
vals, great  armies  of  the  smaller  and  more  prolific  rodents,  which 
usually  spend  their  lives  where  they  were  born,  are  met  with  on 
the  march  from  homes  where  overproduction  has  exhausted  the 
food ;  and  several  of  the  older  American  naturalists  have  described 


I08  THE  FOUNDATIONS  OF  ZOOLOGY 

the  migration  of  our  gray  squirrels,  although  the  phenomenon  has 
been  most  carefully  studied  in  the  Norwegian  lemmings,  whose 
remarkable  migrations  have  figured  in  literature  for  centuries. 

The  lemming  is  a  small,  restless,  pugnacious,  and  very  prolific 
rodent,  somewhat  like  a  guinea  pig  in  shape,  which,  at  uncertain 
intervals  of  from  five  to  twenty  years,  migrates  from  its  ordinary 
home  in  the  central  mountains  of  Norway  and  invades  the  low 
lands  so  suddenly  and  in  such  numbers  that  it  is  still  popularly 
believed  to  drop  from  the  sky,  as  in  the  day  of  Olaus  Magnus, 
who  wrote  of  it  in   1490. 

The  great  army  of  lemmings  moves  on  in  a  straight  line  and 
overruns  the  cultivated  country,  swimming  the  lakes  and  rivers, 
and  causing  so  much  destruction  that  a  special  formula  to  be 
used  against  it  was  authorized  by  the  church,  which  attempted  to 
check  its  march  by  exorcism,  as  the  Bishop  of  Montreal  once 
tried  to  exorcise  the  wild  pigeons.  The  lemmings  journey  at 
night,  but  their  march  is  not  continuous,  for  they  make  long 
stops  in  fertile  spots,  where  they  are  even  more  prolific  than  they 
were  at  home,  so  that  they  become  more  and  more  numerous, 
although  they  are  attended  by  bears  and  wolves,  dogs,  eagles, 
hawks,  owls,  and  other  birds  and  beasts  of  prey,  and  although 
even  the  cattle  and  reindeer  are  said  to  kill  and  eat  them.  The 
march  may  last  for  several  years,  but  as  they  never  go  back,  but 
continue  to  move  forwards,  they  at  last  reach  the  ocean,  and, 
attempting  to  swim  this,  as  they  have  the  rivers  in  their  course, 
all  are  drowned,  like  the  rats  of  Hamlin. 

While  the  migration  of  the  lemmings  is  undoubtedly  due  to 
scarcity,  it  is  difficult  to  understand  its  use,  for  the  only  ones 
which  profit  by  it  are  the  ones  which  have  it  least  developed  and 
stay  at  home  in  the  mountains,  although  it  may  have  been  useful 
before  the  low  lands  were  occupied  by  man,  who  now  destroys 
the  stragglers  and  prevents  them  from  scattering  and  finding  per- 
manent homes. 

While  the  determining  influence  is  the  scarcity  of  food  which 
comes  from  crowding,  we  have  no  reason  to  believe  that  the 
lemmings  consciously  and  deliberately  set  out  in  search  of  a  new 
feeding  ground,  or  that  they  have  traditions  of  the  rich  low  lands 
which  attract  them  as  the  wealth  and  luxury  of   China  and  Meso- 


MIGRATION  IN  ITS  BEARING    ON  LAMARCKISM  109 

potamia  and  Asia  Minor  and  the  Roman  Empire  attracted  the 
Tartars  and  Scythians  and  Goths  from  their  sterile  and  desolate 
northern  lands  into  the  fertile  homes  of  southern  civilization. 
Their  journeys  are  no  doubt  initiated  by  an  unconscious  impulse, 
which,  before  it  brought  them  into  contact  with  man,  was  useful 
in  some  way  to  the  species ;  and  this  seems  to  be  true  also  of  the 
migrations  of  certain  prolific  species  of  grasshoppers  and  locusts 
which,  inhabiting  sandy  and  sterile  regions,  often  overflow  the 
limits  of  their  natural  home,  and  invade  more  fertile  regions 
where  they  are  not  usually  found.  While  there  is  no  reason  to 
suppose  that  these  movements  are  undertaken  through  a  deliber- 
ate intention  to  find  new  feeding  grounds,  lack  of  food  is  no 
doubt  the  chief  factor  in  the  development  of  the  migratory 
instinct  of  rodents,  as  well  as  that  of  grasshoppers  and  locusts, 
which  resemble  birds  in  their  ability  to  make  long  journeys  on 
the  wing  without  rest.  The  African  locust  has  been  met  with  at 
sea,  in  great  clouds,  more  than  twelve  hundred  miles  from  land,  and 
the  species  sometimes  wanders  from  its  home  in  Africa  to  England. 
While  the  movements  of  rodents  and  insects  show  that  the 
search  for  food  has  much  to  do  with  migration,  they  lack  most 
of  the  features  which  make  the  migration  of  birds  so  remarkable. 
They  occur  at  irregular  intervals,  while  the  movements  of  birds 
are  almost  as  regular  as  the  almanac ;  for  while  sea-birds  seem 
much  exposed  to  storms,  the  days  of  their  arrival  and  departure 
may  be  predicted  with  as  much  certainty  as  if  they  were  satellites 
revolving  around  the  earth.  "  Foul  weather  and  fair,  hot  or  cold ; 
the  pufifins  make  their  appearance  at  the  proper  day  as  promptly 
as  if  they  were  moved  by  clock  work."  While  the  course  of  the 
migration  of  rodents  and  locusts  is  determined  by  conditions  so 
complicated  and  irregular  that  they  may  be  called  accidental,  the 
northward  journey  of  birds  is  often  directed  to  a  definite  spot 
thousands  of  miles  from  the  starting-point,  and  the  resemblance 
between  irregular  migrations  in  search  of  food  and  the  migrations 
of  birds  is  too  imperfect  to  tell  us  much  about  the  latter,  which 
is  much  more  like  the  movements  of  certain  fishes  like  the  shad, 
which  at  a  definite  season  enters  upon  a  journey  along  a  definite 
path  to  a  spot  hundreds  of  miles  away,  to  return  again  after  the 
purpose  of  the  journey  is  accomplished. 


no  THE  FOUNDATIONS  OF  ZOOLOGY 

Since  the  number  of  shad  which  enter  a  river  in  the  spring 
are  out  of  all  proportion  to  its  resources  as  a  feeding  ground,  we 
might  say  of  them,  as  we  are  disposed  to  say  of  birds,  that  they 
leave  their  birthplace  in  search  of  food ;  but  as  they  find  so  little 
proper  food  in  the  rivers  that  it  may  be  said  with  almost  literal 
exactness  that  they  make  their  journey  fasting,  it  is  quite  plain 
that  this  is  the  wrong  point  of  view;  that  we  must  believe  that 
they  enter  the  rivers  to  lay  their  eggs,  and  that  we  must  see  in 
this,  and  not  in  the  return  journey  to  the  ocean,  the  purpose  of 
their  migration. 

As  the  shad  is  a  marine  fish  which  does  its  eating  at  sea, 
and  as  its  visits  to  fresh  water  are  only  for  the  purpose  of  repro- 
duction, the  numbers  which  make  their  way  up  the  rivers  bear 
no  comparison  to  the  capacity  of  the  streams  for  supplying  them 
with  food.  When  it  visits  our  coast  in  the  spring,  it  enters  the 
mouths  of  our  rivers  in  great  schools,  and  it  journeys  up  them 
to  a  surprising  distance ;  the  total  length  of  the  journey  from  the 
sea  to  the  spawning  ground  and  back  again  often  exceeds  a 
thousand  miles,  and  this  journey  is  made  almost  or  quite  without 
food.  Many  of  them,  and  among  these  the  largest  ones,  go  on 
and  on  until  they  reach  some  insurmountable  obstacle,  such  as  a 
water-fall  or  a  dam,  or  until  they  reach  the  sources  of  the  river. 
Before  dams  were  built  in  the  Susquehanna  River,  many  shad 
which  entered  the  Chesapeak  Bay  at  the  Capes  continued  their 
long  fasting  journey  across  Virginia  and  Maryland  and  Pennsyl- 
vania, into  the  state  of  New  York,  and  travelled  through  more 
than  five  hundred  miles  of  inland  waters  before  they  reached  the 
end  of  their  journey  upwards. 

Fragments  of  Indian  pottery,  stamped  with  a  pattern  made 
by  the  impression  of  a  shad's  backbone  have  been  found  in 
southern  New  York,  and  the  number  of  stone  net-sinkers  which 
have  been  picked  up  in  the  Wyoming  valley  shows  that  the 
Indians  had  known  and  used  the  shad-fisheries  long  before  the 
first  white  settlers  found  them  at  work  with  their  rude  seines. 
In  the  early  part  of  this  century,  before  canals  and  the  dams 
which  supply  them  were  made,  there  were  forty  fishing  stations 
beyond  the  forks  of  the  Susquehanna  in  northern  Pennsylvania,  and 
some  of  them  were  worth  from   $1000  to    $1200  a    year    to   their 


MIGRATION  IN-  ITS  BEARING   ON  LAMARCKISM  III 

owners,  at  a  time  when  money  represented  much  more  than  it 
does  now.  There  is  a  record,  which  seems  trustworthy,  of  the 
capture,  at  a  single  haul,  of  ten  thousand  shad  at  one  of  these 
fisheries,  on  Fish  Island,  near  Wilkesbarre.  Dams  across  the  river 
have  excluded  the  shad  from  more  than  two  hundred  miles  of  the 
course  of  the  Susquehanna,  and  the  profitable  fisheries  now  reach 
for  only  a  few  miles  above  the  boundary  of  Maryland,  while  the 
shad  are  excluded  from  many  of  the  best  breeding  grounds,  which 
are  the  sandy  flats  near  the  shores  of  streams  and  the  sand-bars 
which  lie  in  their  course.  The  fishes  run  up  on  to  these  places 
in  pairs,  in  the  early  evening,  after  sunset,  and  the  eggs  are 
thrown  into  the  water  while  the  fishes  are  swimming  about,  but 
they  soon  sink  to  the  bottom,  and  develop  very  rapidly.  The 
average  number  of  eggs  is  about  twenty-five  thousand,  but  a 
hundred  thousand  have  been  obtained  from  a  single  large  shad. 

Few  adult  shad  escape  all  the  dangers  of  their  journey,  and 
these  few  are  so  battered  and  emaciated  that  they  are  of  no 
value  as  food,  and  they  are  unknown  in  our  markets,  which  are 
supplied  with  those  which  are  caught  on  their  way  upward.  The 
young  fishes  remain  in  the  rivers  until  late  in  the  fall,  feeding  upon 
small  Crustacea,  the  larvae  of  insects,  the  young  of  other  fishes,  and 
other  minute  active  animals,  and  they  grow  to  a  length  of  two  or 
three  inches  by  November,  when  they  leave  our  waters  for  the  ocean. 

The  shad  is  a  marine  fish  which  has  gradually  acquired  the 
habit  of  depositing  its  eggs  in  fresh  water,  out  of  the  reach  of 
the  innumerable  enemies  which  abound  on  the  shoals  and  sand-bars 
of  the  seashore.  As  the  eggs  are  abandoned  by  their  parents  as 
soon  as  they  are  laid,  prolonged  residence  at  the  breeding  place  is 
not  necessary,  and  the  shad  has  thus  been  able  to  utilize  locali- 
ties which  supply  no  proper  food,  and  are  unfit  for  prolonged 
residence.  If  it  were  compelled  to  incubate  its  eggs  and  to 
guard  and  protect  and  feed  its  nestlings  like  a  bird,  it  would 
have  been  restricted  to  some  breeding  place  where  conditions  are 
favorable  to  a  more  prolonged  residence,  and  we  should  then  feel 
something  of  the  same  tendency  to  call  its  birthplace  its  true 
home  that  we  have  in  the  case  of  birds.  We  should  refer  the 
migration  to  this  place  as  the  starting-point,  and  should  try  to 
find  some  reason  why  they  spend  part  of  the  year  elsewhere. 


112  THE  FOUNDATIONS   OF  ZOOLOGY 

Most  animals  owe  their  existence  to  the  occurrence,  in  their 
natural  home,  of  all  that  their  life  requires,  but  the  power  to 
traverse  great  distances  at  great  speed,  and  to  pass  over  all  the 
barriers  of  land  and  water,  joined  to  their  indifference  to  changes 
of  temperature,  permits  birds  to  divide  their  time  between  two 
widely  separated  regions;  and  whether  the  choice  be  conscious  or 
unconscious,  the  breeding  places  of  migratory  birds  are  selected 
on  account  of  their  safety  and  not  because  they  furnish  all  that 
is  needed  for  a  permanent  home. 

If  we  believe,  with  Professor  Marsh,  that  the  power  of  flight 
was  acquired  by  birds  after  they  became  arboreal,  we  must  look 
for  the  ancestral  home  of  the  migratory  birds  in  the  great  tropi- 
cal and  sub-tropical  forests,  where  arboreal  reptiles  and  arboreal 
mammals  still  abound,  nor  can  we  believe  the  great  armies  of 
.northern  birds  which  find  abundant  food  in  southern  lands  in 
winter,  are  driven  out  by  scarcity  on  the  approach  of  spring. 
Enemies  are  numerous  in  the  tropics,  but  no  animals  are  more 
alert,  or  have  sharper  senses,  or  better  means  of  escape,  than 
birds,  and,  trusting  to  their  powers  of  flight,  and  their  quick  sight 
and  hearing,  they  venture  into  danger  with  confidence,  for  the 
great  charm  of  birds  to  us  is  the  fearlessness  with  which  they 
approach  man,  who  is  the  most  dreaded  enemy  of  all  other  verte- 
brates. But  while  this  is  eminently  true  of  adult  birds,  its  opposite 
is  true,  in  even  greater  degree,  of  nestlings ;  for  no  animals  are 
at  the  same  time  more  helpless  and  more  exposed  to  danger  than 
many  young  birds,  while  the  exposed  eggs  are  of  course  abso- 
lutely helpless,  and  very  tempting  and  attractive  to  enemies, 
although  there  is  no  group  of  animals  in  which  the  safety  of  the 
eggs  and  young  is  more  important.  As  their  eggs  are  very 
large  and  heavy,  a  high  birth-rate  is  incompatible  with  flight, 
and  the  preservation  of  each  species  imperatively  demands  that 
every  ^^^  shall  be  cared  for  with  unceasing  solicitude ;  for 
while  in  other  animals  increased  danger  to  eggs  or  young  may 
be  met  and  compensated  by  an  increase  in  the  birth-rate,  the 
birth-rate  of  birds  cannot  be  much  increased  without  a  corre- 
sponding restriction  of  the  power  of  flight.  Every  one  knows 
how  quickly  birds  may  be  exterminated  by  the  destruction  of 
their  eggs  or  young,  and  the  low  birth-rate  of  all  birds  of  power- 


MIGRATION  IN-  ITS  BEARING   ON  LAMARCKISM  II3 

ful  flight  is  a  sufficient  reason  for  migration,  for  at  the  same 
time  that  their  fitness  for  flight  Hmits  the  birth-rate,  it  permits 
them  to  seek  nesting  places  beyond  the  reach  of  their  enemies ; 
and  as  there  is  rigorous  selection  of  the  nestlings  which  are  born 
in  safe  nests,  it  is  easy  to  understand  how  the  instinct  has  been 
gradually  acquired  by  selection,  and  how,  as  it  has  become  more 
and  more  firmly  fixed,  and  as  the  safety  of  the  eggs  and  young 
has  become  assured  by  the  remoteness  and  isolation  of  the  nests, 
the  birth-rate  has  been  still  more  reduced,  and  the  power  of 
flight  still  more  extended.  Many  sea-birds,  which  make  their 
nests  on  desolate  rocks  in  mid-ocean,  lay  only  a  single  Qg'g  each 
year  and  exhibit  the  power  of  flight  in  its  highest  perfection. 
The  power  of  the  storm-petrel  to  wander  is  as  boundless  as  the 
ocean,  and  while  it  lays  only  a  single  Q%.Z,  there  is  reason  to 
believe  that  it  is  the  most  prolific  of  all  birds,  for  the  number  of 
individuals  is  said  to  be  greater  than  in  any  other  genus. 

We  cannot  believe  that  all  migratory  birds  inherit  the  habit 
from  some  common  parent  which  was  migratory,  nor  is  it  proba- 
ble that,  in  all  cases,  it  owes  its  origin  to  the  same  influences; 
but  if  the  view  here  advanced  be  correct,  we  must  believe  that, 
in  most  migratory  birds,  it  has  been  brought  about  by  the  needs 
which  arise  in  connection  with  reproduction,  and  not  by  the  sup- 
ply of  food,  and  that  the  winter  home  in  tropical  and  sub- 
tropical regions,  and  not  the  birthplace  of  modern  birds,  must 
be  regarded  as  the  original  starting-point  for  the    migratory  habit. 

While  Wallace  was  the  first  to  recognize  the  importance  of 
selection  in  the  formation  of  this  as  well  as  other  habits  and 
instincts,  he  seems  to  regard  selection  alone,  without  the  assist- 
ance of  geological  changes,  as  inadequate  to  explain  all  the  facts 
of  migration.  He  says:  "It  appears  to  me  probable  that  here, 
as  in  so  many  other  cases,  survival  of  the  fittest  will  be  found 
to  have  had  a  powerful  influence.  Let  us  suppose  that  in  any 
species  of  migratory  birds,  breeding  can  as  a  rule  be  only  safely 
accomplished  in  a  given  area ;  and  farther,  that  during  the 
greater  part  of  the  rest  of  the  year  sufficient  food  cannot  be 
obtained  in  that  area.  It  will  follow  that  those  birds  which  do 
not  leave  the  breeding  area  at  the  proper  season  will  suffer,  and 
ultimately  become  extinct;   which  will    also   be   the   fate    of   those 


114  THE  FOUNDATIONS   OF  ZOOLOGY 

which  do  not  leave  the  feeding  area  at  the  proper  time.  Now 
if  we  suppose  that  the  two  areas  were,  for  some  remote  ancestor 
of  the  existing  species,  coincident,  but  by  geological  or  climatic 
changes  gradually  diverged  from  each  other,  we  can  easily  under- 
stand how  the  habit  of  incipient  and  partial  migration  at  the 
proper  season  would  at  last  become  hereditary,  and  so  firmly 
fixed  as  to  become  what  we  term  an  instinct.  It  will  probably 
be  found  that  every  gradation  still  exists  in  various  parts  of  the 
world,  from  a  complete  coincidence  to  a  complete  separation  of 
the  breeding  and  subsistence  areas,  and  when  the  natural  history 
of  a  sufficient  number  of  species  is  thoroughly  worked  out,  we 
may  find  every  link  between  species  which  never  leave  a  re- 
stricted area  where  they  breed  and  live  the  whole  year  round, 
to  those  other  cases  in  which  the  two  areas  are  absolutely 
separated." 

Modern  zoology  owes  its  basis  to  the  work  of  Wallace  and  Dar- 
win on  the  distribution  of  birds,  which,  in  their  hands,  has  led  to 
a  revolution  in  our  conceptions  of  nature,  and  has  given  so  much 
weight  to  all  their  utterances  on  the  subject  that  no  one  would 
venture  to  differ  from  them  inconsiderately,  although,  when  we 
try  to  interpret  the  language  which  Wallace  here  uses  in  the 
light  of  his  other  works,  it  seems  very  doubtful  whether  he  has 
carefully  weighed  the  words  in  which  he  here  states  that  "  the 
habit  of  incipient  and  partial  migration "  may  "  at  last  become 
hereditary."  We  must  also  bear  in  mind  that  migration  and  dis- 
tribution are  distinct  phenomena,  and  that  while  the  geographical 
distribution  of  birds  shows  clear  indications  of  the  effect  of  past 
geological  changes  in  the  distribution  of  land  and  water,  migra- 
tory birds,  like  other  birds,  are  kept  from  invading  other  provinces 
than  their  own  by  competitors  and  enemies,  rather  than  by  geo- 
graphical barriers.  As  so  many  birds  move  towards  the  poles  of 
the  earth  to  lay  their  eggs,  and  towards  the  equator  to  spend 
the  winter,  the  view  that  their  breeding  area  and  their  subsistence 
area  have  gradually  become  widely  separated  by  changes  of  cli- 
mate seems  probable  at  first  sight,  but  this  rule  is  not  universal, 
for  many  of  the  great  breeding  grounds  of  sea-birds  are  in  tem- 
perate or  tropical  waters.  The  petrels  and  albatrosses,  terns,  gulls, 
and  many  other  birds  pass  most  of  their  lives    scattered   over   the 


MIGRATION  IN  ITS  BEARING   ON  LAMARCKISM  II5 

surface  of  the  ocean,  but  this  affords  no  nesting  place,  while  the 
wastes  of  water  which  keep  carnivorous  mammals  and  reptiles 
and  other  enemies  of  nesting  birds  from  approaching  the  remote 
and  desolate  rocks  and  sand-bars  of  the  open  ocean,  are  no  ob- 
stacle to  them.  These  spots  are  so  secure  that  birds  born  in 
them  are  much  more  likely  than  those  born  on  the  shores  of  in- 
habited lands  to  survive,  so  that  it  has  come  about  that  all  the 
modern  members  of  these  groups  are  descended  from  ances- 
tors who  shunned  the  dangerous  nesting  places,  not  because 
acquired  characters  have  become  inherited,  nor  because  their 
feeding  ground  and  their  nesting  places  have  been  drawn  apart 
by  geological  changes,  but  because  those  which  did  not  instinc- 
tively seek  safe  places  for  the  few  eggs  which  are  all  that  their 
fitness  for  continuous  and  rapid  flight  permits  have  been  extermi- 
nated. These  birds  now  gather  from  all  parts  of  the  ocean,  on 
the  few  widely  scattered  rocks  and  islands  where  their  young  are 
safe,  and  the  periodic  assemblies  of  innumerable  multitudes  of 
wandering  sea-birds  in  their  "  rookeries "  are  true  migrations,  for 
they  are  as  regular  as  the  almanac  in  the  time  of  arrival  and 
departure,  although  their  feeding  ground  is  almost  as  extensive 
as  the  ocean,  and  although  the  food-supply  has  nothing  to  do 
with  their  movements,  and  although  they  do  not  reach  the  rook- 
eries by  a  single  path. 

In  this  case  the  needs  of  reproduction  are  the  controlling  influ- 
ence, and  the  site  of  the  rookery  has  been  fixed  by  its  safety ;  and 
while  it  is  difficult  to  say  how  far  the  birds  are  guided  by  experi- 
ence of  the  danger  of  other  places,  the  well-known  tameness  of 
sea-birds  in  their  breeding  places,  and  their  apparent  ignorance  of 
the  existence  of  enemies,  seem  to  show  that  they  are  quite  uncon- 
scious of  the  advantages  of  the  chosen  spot,  and  that  they  resort 
to  it  automatically  or  naturally,  since  they  owe  their  existence  to 
its  isolation  and  its  safety. 

Zoologists  are  far  too  ready  to  resort  to  the  boundless  fields 
for  speculation  which  geology  affords,  and  Crotch  has  gravely  sug- 
gested that  the  migration  of  the  lemmings,  and  their  death  in  the 
waters  of  the  ocean,  may  be  due  to  their  efforts  to  reach  the  lost 
Atlantis  which  their  ancestors  inhabited  during  the  Miocene  period; 
although  this  opinion  has  no  better  basis  than  the  belief  of  Olaus 


Il6  THE  FOUND ATTONS  OP  ZOOLOGY 

Magnus  that  they  rain  down  from  the  clouds,  where  they  are  devel- 
oped from  decomposing  exhalations  impregnated  with  the  semen 
of  rats. 

It  is  easy  to  understand  how  birds  near  the  northern  limit  of 
their  range  may  invade  the  territory  of  those  whose  home  is  a  little 
further  south,  and  compete  with  them  for  food  as  this  becomes 
scarce  on  the  approach  of  winter,  and  how  this  movement  spreads 
until  all  the  members  of  the  species  are  involved,  although  many 
of  these  might  have  been  able  to  satisfy  all  the  necessities  of  life 
for  some  time  longer  in  their  breeding  grounds,  if  they  had  been 
undisturbed. 

We  have  noted  that  this  has  commended  itself  to  northern  natu- 
ralists as  a  sufficient  reason  for  the  acquisition  of  the  migratory 
habit,  and  that  the  fondness  for  their  birthplace  which  is  so  strongly 
developed  in  birds  has  been  thought  enough  to  draw  them  back; 
but  the  love  of  home  is  itself  a  result  of  natural  selection,  and  the 
necessity  for  finding  safe  places  for  the  eggs  and  young  enough 
to  account  for  the  origin  of  migration  without  the  aid  of  geological 
changes. 

Even  if  we  know  little  as  to  the  means  by  which  birds  find  their 
way  over  land  and  water,  we  know  as  a  fact  that  they  are  able  to 
do  so ;  and  we  also  know  that  the  instinct  which  leads  them  to 
seek  safe  places  for  their  nests  is  so  strongly  implanted  in  their 
nature  that  centuries  of  domestication  weaken  it  but  little,  for  it  is 
still  as  strong  in  the  guinea  fowl  and  the  turkey  and  the  hen  as  it 
is  in  wild  birds.  As  birds  of  powerful  flight  have  a  range  of  choice 
in  the  selection  of  places  for  their  nests  which  is  almost  as  wide  as 
the  earth  itself,  it  is  not  surprising  that  the  continual  destruction 
of  those  born  in  the  least  safe  nests  has  at  last  resulted  in  the  sur- 
vival of  the  ones  which  build  their  nests  thousands  of  miles  away 
from  their  ancestral  home. 

While  most  writers  on  the  subject  have  thought  that  migration 
had  its  origin  in  an  annual  journey  which,  while  short,  was  definite 
for  all  the  members  of  the  species,  and  while  they  have  felt  forced 
to  call  in  the  aid  of  geology  to  account  for  the  gradual  separation 
of  the  two  termini,  and  the  length  of  the  journey  from  one  to  the 
other,  the  hypothesis  of  geological  change  seems  gratuitous  and 
unnecessary,  since   the    known    habits    and   instincts  and  needs  of 


MIGRATION  IN  ITS  BEARING   ON  LAMARCKISM  WJ 

the  birds  are,  in  themselves,  a  sufficient  explanation  of  all  the 
broader  and  more  general  characteristics  of  migration. 

It  seems  much  more  simple,  and  much  more  consistent  with 
our  knowledge  of  the  past  history  of  living  things,  in  general,  to 
believe  it  had  its  origin  in  an  intense  but  geographically  indefinite 
impulse,  which  led  birds  to  scatter  at  the  breeding  season,  and  to 
hunt  out  safe  hiding  places  for  their  nests,  and  that,  as  enemies 
also  improved  in  power  to  find  the  most  accessible  nests,  the 
instinct  gradually  shaped  itself  into  definiteness  through  selection 
and  extermination,  until,  at  last,  safe  breeding  grounds  far  away 
from  home,  and  far  away  from  the  enemies  which  there  abounded, 
have  become  established,  and  until  many  species  and  all  the  sur- 
viving members  of  each  species  have  come  to  share  the  impulse 
to  resort  to  these  selected  breeding  places  on  the  approach  of  the 
period  of  sexual  excitement,  and  to  follow  the  same  path  between 
points  far  apart ;  that  the  increasing  safety  of  the  eggs  and  young 
has  permitted  a  low  birth-rate,  and  the  improvement  by  selection 
of  the  power  of  rapid  and  long-continued  flight ;  and  that  this  has, 
in  its  turn,  permitted  the  migration  to  become  longer  and  longer, 
and  more  and  more  protective  to  the  eggs  and  young. 

The  history  of  migratory  birds  has  been  long  and  complicated ; 
and  there  has  been  time  for  great  changes  in  the  distribution  of 
land  and  water,  and  for  changes  of  climate,  and  these  have,  no 
•doubt,  left  some  permanent  impression  on  the  habits  of  birds. 

They  have  not  eluded  all  their  enemies,  for  predaceous  birds  and 
their  prey  are  found  together  in  both  the  summer  and  the  winter 
homes.  New  ways  to  escape  enemies  and  new  ways  to  find  food 
are  as  important  as  they  ever  were,  and  birds  undoubtedly  have 
capacity  for  improving  by  experience  and  for  forming  new  habits. 

All  these  influences  have,  no  doubt,  had  and  still  have,  their 
•effect  on  migration,  so  that  the  history  of  the  subject  is  very 
complicated ;  although  it  seems  clear  that  its  broader  outlines 
admit  of  explanation  by  natural  selection  without  recourse  to 
geology  or  to  the  inheritance  of  the  direct  effects  of  nurture. 

In  conclusion  I  wish  to  remind  the  reader  that  our  present 
interest  in  migration  lies  in  its  value  as  an  illustration  of  the 
general  law  that  the  adaptations  of  nature  are  for  the  good  of 
the  species  and  not  for   the  benefit   of   the   individual.     This  law 


Il8  THE  FOUNDATIONS  OF  ZOOLOGY 

is  universal,  but  since  the  welfare  of  the  species  is  usually  iden- 
tical with  that  of  the  constituent  individuals  it  is  not  obvious 
unless  the  good  of  the  species  demands  the  sacrifice  of  individuals. 

Long  journeys  are  hazardous.  Every  California  salmon  which 
enters  upon  the  long  journey  to  the  breeding  ground  is  destroyed, 
and  the  whole  race  is  wiped  out  of  existence  for  the  good  of 
generations  yet  unborn.  Very  few  shad  ever  return  to  the  ocean, 
and  storm  and  accident  and  ruthless  enemies  work  their  will  on 
the  migrating  birds  and  decimate  them  without  mercy,  yet  the 
dangerous  return  to  safe  breeding  grounds  still  goes  on  in  order 
that  children  which  are  yet  unborn  may  survive  to  produce  chil- 
dren in  their  turn. 

The  safeguards  which  nature  throws  around  eggs,  and  infants, 
and  immature  animals,  and  the  indifference  to  the  fate  of  the 
mature  animals  which  seems  to  be  exhibited  by  the  influences 
which  have  shaped  species  into  fitness  for  their  environment,  are 
facts  which  must  never  be  lost  sight  of;  for  if  we  forget  them, 
our  attempts  to  understand  the  history  of  the  properties  of  living 
things  or  the  meaning  of  our  own   nature  are  certain  to   mislead. 

Transition  from  the  migration  of  the  salmon  to  the  altruistic 
moral  sense  of  ethical  man  may  seem  abrupt,  yet  the  two  subjects 
may  not  be  so  far  apart  as  they  seem,  if  the  natural  attributes 
of  every  living  thing  are  primarily  for  the  good  of  others,  as  I 
have  sought  to  show  in  the  last  two  lectures. 

The  fish  owes  its  existence  to  the  migratory  impulse,  which  is 
therefore  useful,  although  it  is  not  useful  to  the  fish  that  migrates. 
It  has  a  utilitarian  basis  and  a  utilitarian  history ;  but  if  the  salmon 
were  enlightened,  its  actions  would  exhibit  enlightened  self-sacri- 
fice and  not  enlightened  selfishness. 

Many  good  and  thoughtful  people  hold  that  proof  that  our 
moral  sense  has  had  a  natural  history  would  have  very  dreadful 
consequences ;  that  it  would  show  that  duty  is  not  duty,  right 
and  wrong  neither  right  nor  wrong,  and  that  the  significance 
man  has  attributed  to  this  part  of  his  nature  a  mistake. 

I  cannot  believe  anything  so  beneficial  and  wholesome  as  the 
increase  of  natural  knowledge  can  lead  to  disaster,  and  while 
I  do  not  suppose  my  own  inability  to  see  why  these  dreadful 
consequences  should   follow   will    count    for   much,  this  inability  is 


MIGRATION  IN  ITS  BEARING   ON  LAMARCKISM  1 19 

real;  for  while  I  am  convinced  that  the  moral  sense  owes  its 
existence  to  its  utility,  I  fail  to  see  what  bearing  its  history  has 
on  its  significance  or  its  value. 

They  who  perceive  that  all  the  nature  of  living  things  is  prima- 
rily for  the  good  of  others,  and  that  the  poison  of  serpents  and 
the  ferocity  of  the  tiger  are  as  free  from  selfishness  as  the  industry 
of  the  bee  or  the  mother's  love  for  her  child,  can  no  longer  wonder 
if  something  in  our  own  nature  should  impel  us  to  acts  which 
are  not  to  our  personal  liking  or  advantage ;  nor  need  they  fear 
lest  the  discovery  of  the  natural  history  of  the  moral  sense  may 
destroy  its  value. 

Should  it  not  rather  "  seem  to  follow  that  reasonable  creatures 
were,  as  the  philosophical  Emperor  observes,  made  one  for  another ; 
and,  consequently,  that  man  ought  not  to  consider  himself  as  an 
independent  individual,  whose  happiness  is  not  connected  with  that 
of.  other  men ;  but  rather  as  a  part  of  a  whole,  to  the  common 
good  of  which  he  ought  to  conspire,  and  order  his  ways  and 
actions  suitably,  if  he  would  live  according  to  nature "  ?  "  Will  it 
not  follow  that  a  wise  man  should  consider  and  pursue  his  private 
good,  with  regard  to,  and  in  conjunction  with,  that  of  other  men  ? 
though,  indeed,  the  sympathy  of  pain  and  pleasure,  and  the 
mutual  affections  by  which  mankind  are  knit  together,  have  been 
always  allowed  a  plain  proof  of  this  point;  and  though  it  was 
the  constant  doctrine  of  those  who  were  esteemed  the  wisest  and 
most  thinking  men  among  the  ancients."^ 

1  Berkeley,  "Alciphron,"  I.  16  and  II.   13. 


LECTURE    VI 

ZOOLOGY,    AND   THE   PHILOSOPHY 
OF   EVOLUTION 


"I  have  nothing  to  say  to  any  Philosophy  of  Evolution.  .  .  .  Attempts  to  construct 
such  a  philosophy  may  be  ...  .  useful,  but  in  my  judgment  they  are  ....  premature." 
—  Huxley  :  "  Collected  Essays,"  V. 


LECTURE    VI  — Part    I 

ZOOLOGY,  AND  THE   PHILOSOPHY  OF   EVOLUTION 

The  facts  given  in  the  last  two  lectures  seem  to  show  that 
we  cannot  expect  much  from  the  "  Lamarckian  factors,"  even  if 
they  should  prove  to  be  factors ;  and  while  this  impression  may 
be  wrong,  it  seems  to  be  the  rational  frame  of  mind  until  it  has 
proved  wrong. 

He  who  follows  the  current  literature  of  zoology  finds  that 
many  writers  assure  him,  in  effect,  that  the  years  which  Darwin 
and  Wallace  gave  to  hard  labor  on  the  problem  of  species  were 
thrown  away,  since  all  they  tried  to  find  out  by  hard  work  might 
have  been  deduced  from  the  Philosophy  of  Evolution. 

We  were  warned,  long  ago,  that  "whoever,  unable  to  doubt 
and  eager  to  affirm,  shall  establish  principles,  and,  according  to 
the  unmoved  truth  of  these,  shall  reject  or  receive  others,  ...  he 
shall  exchange  things  for  words,  reason  for  insanity,  the  world  for 
a  fable,  and  shall  be  incapable  of  interpreting." 

In  "philosophy"  current  history  is  sometimes  ancient  history, 
and  the  ardent  disciples  of  "  philosophers  "  who,  in  modest  earnest- 
ness, undertake  to  formulate  the  scientific  knowledge  of  their  day, 
often  become  bolder  than  their  teachers,  and,  growing  arrogant 
and  reckless  with  success,  find  at  last  that  they  have  sold  their 
birthright  in  nature  for  what  proves,  when  examined,  to  be  na 
better  than  a  mess  of  pottage. 

The  evidence  that  living  matter  is  continuous,  from  beginning 
to  end,  is  so  conclusive  that  it  convinces  all  who  know  its  value. 
All  living  things  are  one  by  birth,  and  the  system  of  living  nature 
is,  historically,  a  unit,  a  consistent  whole  ;  not  a  collection  of  isolated 
and  independent  species.  How  does  it  happen,  then,  that  at  every 
.point  in  its  history,  we  find    it  divided  into  detached  groups,  sep- 

123 


124  THE  FOUNDATIONS   OF  ZOOLOGY 

arated  by  gaps,  and  characterized  by  fitness  ?  Why  is  the  system 
of  living  nature  such  that  we  cannot  picture  it  as  a  circle,  spread- 
ing in  all  directions  from  a  common  centre,  and  growing  wider 
around  its  whole  circumference  ?  Why  is  it  such  that  it  is  more 
exactly  represented  by  a  number  of  growing  radii,  independent  at 
their  outer  ends  ? 

This  is  the  problem  which  Darwin  undertook  to  solve,  by  show- 
ing that  it  results  from  extermination  according  to  a  standard  of 
fitness.  How  does  the  Lamarckian  meet  it  ?  Sometimes  by  deny- 
ing the  existence  of  fitness.  Sometimes  by  asserting,  even  in  the 
same  breath,  that  fitness  is  universal  and  necessary,  and  that  there 
is  no  real  problem. 

He  asserts  that  it  is  the  outcome  or  expression  of  a  deeper 
principle  of  necessary  progress  or  evolution,  which  must  result  in 
fitness.  The  tendency  to  regard  natural  selection  as  more  or  less 
unnecessary  and  superfluous,  which  is  so  characteristic  of  our 
day,  seems  to  grow  out  of  reverence  for  the  all-sufficiency  of  the 
philosophy  of  evolution,  and  pious  belief  that  the  history  of 
living  things  flows  out  of  this  philosophy  as  a  necessary  truth  or 
axiom. 

"  The  inheritance  of  characters  acquired  during  the  life  of  the 
individual  is  an  indispensable  axiom  of  the  monistic  doctrine  of 
evolution."  ^ 

The  writer  yields  to  no  one  in  admiration  of  the  doctrine  of  evo- 
lution. So  far  as  it  is  a  scientific  generalization  from  our  know- 
ledge of  nature,  it  is  one  of  the  greatest  triumphs  of  the  human 
mind ;  rivalled  only  by  its  reciprocal,  the  doctrine  of  dissolution. 

Experience  seems  to  show,  very  clearly,  that  our  system  of 
nature  is,  on  the  whole,  moving  towards  what  commends  itself  to 
our  minds  as  evolution,  or  progress  to  greater  and  greater  per- 
fection. While  there  is  just  as  much  evidence  that  each  step  in 
evolution  is  also  a  step  toward  dissolution,  we  have  the  same 
rational  ground  for  expecting  that  this  movement  will  continue, 
without  any  sudden  radical  change,  that  we  have  for  other  expec- 
tations which  we  base  on  knowledge  of  nature. 

So  far  as  the  doctrine  of  evolution  is  based  on  knowledge,  it  is 
not  only  a  part,  but  one  of  the  most  valuable  and  suggestive  parts 

^  Haeckel,  "  Monism,"  p.  96. 


ZOOLOGY,   AND    THE  PHILOSOPHY  OF  EVOLUTION        12$ 

of  the  system  of  science,  for  the  scientific  law  of  evolution  is  part 
of  science ;  but  the  philosophy  of  evolution  is  held  by  many  as  a 
creed,  superior  to  and  able  to  direct  science.  As  men  of  science, 
we,  like  Huxley,  have  "nothing  to  say  to  any  philosophy  of 
evolution,"  except  so  far  as  it  stands  in  the  way  of  scientific 
progress. 

We  are  sometimes  told  that  while  the  other  idols  of  which 
Bacon  warned  us  are  still  worshipped,  the  idols  of  the  theatre 
have  been  deserted,  and  their  temples  abandoned ;  although  he 
himself    lays  peculiar  stress  on  their  persistency. 

"  Lastly,  there  are  idols  which  have  crept  into  men's  minds 
from  the  various  dogmas  of  particular  systems  of  philosophy,  .  .  . 
and  these  we  denominate  idols  of  the  theatre.  For  we  regard  all 
the  systems  of  philosophy  hitherto  received  or  imagined  as  so 
many  plays  brought  out  and  performed,  creating  fictitious  and 
theatrical  worlds.  Nor  do  we  speak  only  of  the  present  systems, 
or  of  the  philosophy  and  sects  of  the  ancients,  since  numerous 
other  plays    of  a  similar  natin^e   can   still  be   composed^ 

They  who  worship  this  modern  idol  of  the  theatre  hold  that 
everything  which  has  taken  place  and  everything  which  can  take 
place  in  our  universe  is  deducible  from  the  primal  distribution  of 
matter  and  energy.  They  tell  us  that  everything  in  the  past  and 
everything  in  the  future  follows,  of  necessity,  from  this  starting- 
point,  inasmuch  as  it  might  all  have  been  predicted ;  but  while 
science  knows  laws,  —  laws  of  evolution  and  others,  —  it  knows 
no  necessity  except  the  logical  necessity  for  stopping  when  evi- 
dence stops. 

The  evolutionist  tells  us  that  if  we  start  with  a  homogeneous 
universe,  with  all  the  matter  uniformly  distributed,  and  all  the 
energy  kinetic  ;  and  if  any  break  in  this  indefinite  unstable  homo- 
geneity exist  or  be  brought  about,  all  the  rest  must  follow  of 
necessity,  as  a  matter  of  course,  from  the  nature  of  things ;  that 
all  things  must  go  on  along  their  predetermined  course  until  all  the 
matter  shall  have  fallen  into  stable  equilibrium,  and  all  the  energy 
shall  have  become  latent  or  potential. 

As  no  one  can  say  the  basis  for  all  this  is  not  true,  and  as 
it  seems  much  more  consistent  with  scientific  knowledge  than 
other  systems  of  philosophy,  we  must  admit  that,  for  all  we  know 


126  THE  FOUNDATIONS  OF  ZOOLOGY 

to  the  contrary,  it  may  be  true ;  and  we  must  ask  whether,  if 
true,  it  is  any  substitute  for  science ;  although  we  must  remember 
that  there  is  no  end  to  the  things  which,  while  no  one  treats 
them  seriously,  may  nevertheless  be  true. 

All  the  fancies  of  the  poets,  which  do  not  involve  a  con- 
tradiction, may  be  true;  but  while  anything  which  is  not  ab- 
surd may  be  good  poetry,  science  is  founded  on  the  rock  of 
evidence. 

Many  have  found  the  opinion  that  all  nature  is  conscious  and 
endowed  with  volition,  that  the  morning  stars  sing  together,  that 
the  waters  laugh,  that  trees  talk,  and  that  the  wind  bloweth 
where  it  listeth,  worthy  of  belief ;  and  it  is  clear  that  we  can- 
not oppose  any  belief  of  this  sort  by  evidence,  nor  convert  the 
sailor  who  believes  that  the  wind  obeys  his  whistle,  by  asking  for 
proof. 

The  path  of  scientific  progress  is  strewn  with  beliefs  which 
have  been  abandoned  for  lack  of  evidence,  as  burst  shells  strew 
a  battlefield,  and  it  is  our  boast  that  they  are  abandoned,  and 
not  lugged  along  the  line  of  march.  As  a  shell  which  has  failed 
to  burst  is,  now  and  then,  picked  up  on  some  old  battlefield,  by 
some  one  on  whom  experience  is  thrown  away,  and  is  exploded 
by  him  in  the  bosom  of  his  approving  family,  with  disastrous 
results,  so  one  of  these  abandoned  beliefs  may  be  dug  up  by 
the  head  of  some  intellectual  family,  to  the  confusion  of  those 
who  follow  him  as  their  leader. 

So  far  as  the  philosophy  of  evolution  involves  belief  that 
nature  is  determinate,  or  due  to  a  necessary  law  of  jiniversal 
progress  or  evolution,  it  seems  to  me  to  be  utterly  unsupported 
by  evidence,  and  totally  unscientific. 

This  system  of  philosophy  teaches  that,  for  purposes  of  illus- 
tration, our  universe  may  be  compared  to  an  unstable,  homoge- 
neous, saturated  solution ;  which  remains  unchanged  so  long  as 
it  is  undisturbed,  but  crystallizes  when  shaken.  The  process  of 
evolution  must  be  supposed  to  start  with  a  disturbance  or  shock. 
Something,  inherent  in  the  nature  of  things  or  outside,  must  press 
the  button  ;  but  matter  and  its  properties  do  all  the  rest,  just  as 
crystallization  follows  from  the  properties  of  the  solution.  Even 
if    all    this  is  granted,   it  is    not  apparent  that   the    mind   of   the 


ZOOLOGY,   AND    THE  PHILOSOPHY  OF  EVOLUTION        12; 

evolutionist  has  any  power  by  the  aid  of  which  it  could  deduce 
anything  whatever  from  homogeneity,  even  if  it  were  present  at 
the  beginning. 

There  are  homogeneous  solutions  of  sugar  and  homogeneous 
solutions  of  brine,  and  no  one  without  experience  of  similar  facts 
has  any  way  to  tell  what  potencies  are  latent  in  a  solution  except 
by  finding  out.  While  we  find  no  reason  to  suppose  a  homo- 
geneous saturated  solution  has  any  power  to  initiate  anything, 
we  cannot  think  of  it  as  inert.  It  is,  as  it  were,  alive  with  energy, 
and  its  inactivity  is  due  to  the  exact  balancing  of  all  its  powers. 
It  is  prepared  to  spring  into  energetic  action  the  instant  the 
bonds  that  chain  it  are  broken  by  something  that  disturbs  the 
balance  and  sets  its  forces  free. 

So,  too,  the  primeval  homogeneity  of  the  evolutionist  is  imagined 
as  instinct  with  world-producing  energy,  ready  to  evolve  stars  and 
systems  and  worlds  and  oceans  and  continents  and  living  things  and 
men,  and  all  that  is  "  in  the  round  ocean,  and  the  living  air,  and  the 
blue  sky,  and  in  the  mind  of  man,"  the  instant  it  is  set  free;  and 
so  on  to  the  end,  which  will  come  when  all  the  energy  has  worked 
itself  out  in  motion,  and  all  the  matter  has  found  rest  in  stable 
equilibrium. 

Unless  he  who  worships  this  idol  of  the  theatre  is  prepared  to 
assert  that  there  is  only  one  kind  of  indefinite  incoherent  homo- 
geneity; and  unless  he  knows,  in  some  way  of  which  men  of  science 
are  ignorant,  what  sort  of  homogeneous  solution  our  universe  was 
at  the  beginning ;  the  only  way  for  him  to  learn  what  potencies  are 
latent  in  it  is  to  find  out  by  studying  their  products.  It  is  hard  to 
see  how  he  can  deduce  anything  whatever  from  his  necessary  law 
of  universal  progress  except  what  he  discovers.  If  his  premises 
are  admitted,  all  he  can  deduce  from  them  regarding  our  subject 
is  that,  if  he  finds  natural  selection,  the  potency  of  natural  selection 
was  latent  in  his  solution. 

The  philosophy  of  evolution  is  of  no  more  use  as  a  substitute 
for  science  than  any  other  system  of  philosophy,  although  it  is,  no 
doubt,  not  only  the  latest,  but  the  most  consistent  with  our  know- 
ledge of  nature,  and  although  it  may,  for  all  I  know  to  the  contrary, 
be  true.  All  this  fails  to  give  it  any  value  as  a  short  cut  to  natural 
knowledge. 


128  THE  FOUNDATIONS   OF  ZOOLOGY 

The  true  believer  may  say,  however,  that  while  our  finite,  im- 
perfect minds  may  be  unable  to  deduce  anything  from  homo- 
geneity, in  the  absence  of  knowledge  drawn  from  experience,  the 
outcome  of  the  process  must  nevertheless  be  determinate.  As  it 
has  all  come  out  of  the  primeval  homogeneity,  he  says  this  must 
have  contained  it  all  potentially. 

I  am  no  philosopher,  but  this  does  not  seem  obvious  or  neces- 
sary to  me.  Nature,  as  we  know  it,  consists,  in  the  main  of  per- 
mutations and  combinations.  "  I  do  not  know,"  is  one  thing,  and 
"  I  do  know  not "  is  another,  even  if  some  fail  to  discriminate. 

"  It  is  easy  to  perceive  that  the  prodigious  variety  which  ap- 
pears,, both  in  the  works  of  nature  and  in  the  acts  of  men,  and 
which  constitutes  the  greatest  part  of  the  beauty  of  the  universe, 
is  owing  to  the  multitude  of  different  ways  in  which  its  several 
parts  are  mixed  with  or  placed  near  each  other." 

When  we  say  three  dice  can  be  thrown  in  only  two  hundred  and 
sixteen  ways,  all  we  mean  is  that  we  cannot  throw  them  in  any  other 
way.  We  cannot  throw  three  zeros,  or  three  sevens,  in  any  way, 
with  ordinary  dice  without  changing  the  marks;  but  we  cannot 
attribute  to  the  dice  any  latent  capacity  for  being  thrown  in  any 
way,  or  any  capacity  to  do  anything  whatever  as  dice,  even  after 
we  have  been  informed  by  Haeckel  that  "  the  real  maker  of  the 
organic  world  is,  in  all  probability,  a  tetrahedron."  ^ 

Except  for  a  few  odd  thousands  of  quintillions  of  permutations 
and  combinations  no  others  can  be  formed  from  twenty-six  letters, 
and  if  Galileo  means  any  more  than  this  by  his  remark  that  all 
truth  is  contained  in  the  compass  of  the  alphabet;  if  his  words  are 
more  than  figurative ;  if  he  intends  to  assert  that  the  potency  of 
literature  is  latent  in  the  alphabet,  independently  of  an  author,  —  it 
seems  to  me,  with  all  respect  for  Galileo,  that  he  is  talking  non- 
sense; for  while  the  production  of  a  learned  treatise  by  the  fortui- 
tous concourse  of  letters  may  not  be  impossible,  all  the  books  we 
know  of  have  come  about  in  another  way. 

Twenty-eight  figures  are  required  to  express  the  number  of  dis- 
tinct deals  in  whist.  "If  the  whole  population  of  the  world,  say 
one  thousand  millions  of  persons,  were  to  deal  cards  day  and  night 
for  a  hundred  million  years,"  they  might  justify  Sarah  Battle's  criti- 

1"  Monism,"  pp.  27,  28. 


ZOOLOGY,   AND    THE  PHILOSOPHY  OF  EVOLUTION        1 29 

cism  of  the  game,  but  "  they  would  not  in  that  time  have  exhausted 
one  hundredth-thousandth  part  of  the  possible  deals." 

It  is  not  clear  to  me  that  combinations  are  latent  in  the  things 
combined.  In  fact,  the  bearing  of  these  things  on  the  matter 
seems  to  be  negative  and  passive,  rather  than  active  or  positive. 

It  is  not  clear  that,  with  all  their  latent  potency,  a  pack  of 
cards  would  ever  evolve  a  single  hand  without  a  dealer ;  but  if  a 
part  of  the  universe,  so  trivial  and  insignificant,  present  opportu- 
nities so  boundless,  the  matter  and  motion  of  our  universe  may 
present  to  a  dealer  opportunities  for  universes  without  end,  no 
one  like  another.  I  do  not  see  how  one  can  assert  that  anything 
in  the  material  universe  is  necessary  or  predetermined,  except  so 
far  as  it  is  one  among  an  infinite  number  of  possibilities. 

Huxley  tells  us  that,  "  if  the  fundamental  proposition  of  evo- 
lution, that  the  whole  world,  living  and  not  living,  is  the  result  of 
the  mutual  interaction,  according  to  definite  laws,  of  the  forces 
possessed  by  the  molecules  of  which  the  primitive  nebulosity  of 
the  universe  was  composed,"  be  true,  "it  is  no  less  certain  that 
the  existing  world  lay,  potentially,  in  the  cosmic  vapour;  and  that 
a  sufficient  intelligence  could,  from  a  knowledge  of  the  properties 
of  the  molecules  of  that  vapour,  have  predicted,  say,  the  state  of 
the  fauna  of  Great  Britain  in  1868,  with  as  much  certainty  as 
one  can  say  what  will  happen  to  the  vapour  of  the  breath  in  a 
cold  winter's  day." 

The  thoughtful  reader  will  note  that  Huxley's  assertion  that, 
if  this  proposition  be  true,  it  is  no  less  certain  that  the  existing 
world  lay,  potentially,  in  the  cosmic  vapor  is  no  admission  that 
the  proposition  is  true,  or  the  deduction  certain ;  nor  must  we 
forget  that  the  most  notable  and  valuable  characteristic  of  Hux- 
ley's teachings  is  the  declaration,  in  all  his  works,  of  the  truth 
that  the  scientific  basis  of  our  confidence  in  the  order  of  nature  is 
evidence. 

Again  and  again,  in  words  which  are  unmistakable,  he  tells 
us  that,  while  we  may  have  reasonable  confidence  what  to  expect 
from  the  vapor  of  our  breath  in  a  cold  winter's  day,  we  know 
nothing  about  it  except  what  has  happened.  The  scientific  value 
of  our  confidence  depends,  he  tells  us,  on  the  extent  of  our  expe- 
rience   of   the  behavior    of   the    vapor   of   our  breath,    and    similar 

K 


I30  THE  FOUNDATIONS   OF  ZOOLOGY  ' 

bodies,  on  a  cold  day,  or  under  similar  circumstances.  As,  in 
this  case,  our  experience  is  pretty  extensive,  the  deduction  is  safe 
and  reasonable  ;  but  when  a  young  man  who  had  passed  his  life 
in  the  tropics  spent  the  night  on  top  of  a  high  mountain  with 
my  students,  he  was  so  far  from  deducing  anything  from  the 
frosty  morning  air  that  he  was,  at  first,  alarmed  by  the  behavior 
of  the  vapor  of  his  breath. 

If  Huxley  is  right,  —  if  the  logical  basis  for  confidence  in 
nature  is  evidence,  —  it  seems  clear  that  no  amount  of  knowledge 
can  ever  give  it  any  other  basis ;  for  nothing  seems  more  obvious, 
or  more  strictly  logical,  than  our  inability  to  deduce  anythmg 
from  a  single  experience.  The  burnt  child  may  dread  the  fire  as 
much  as  if  it  had  been  burned  twenty  times,  but  the  only  way 
for  it  to  learn  whether,  and  to  what  degree,  its  dread  is  wise 
and  prudent,  without  passing  through  the  slow  and  painful  pro- 
cess of  selection,  is  to  get  knowledge,  for  a  single  experience 
affords  no  basis  for  any  logical  process. 

While  the  emotional  value  of  a  sensation  is,  no  doubt,  limited 
by  inherited  structure,  and  dependent,  to  some  degree,  on  inten- 
sity, its  objective  value  as  knowledge  is  regulated  in  accordance 
with  the  statistical  law  of  probability. 

If  the  history  of  what  we  call  our  universe  were  complete 
from  beginning  to  end ;  if  everything  which  exists  in  it  were 
reduced  to  mechanical  principles,  and  traced  back  to  primitive 
nebulosity,  —  this  history  would  be  only  a  single  experience  in  cos- 
mogony, so  far  as  the  history  of  universes  is  in  question.  If  we 
were  to  find,  somewhere,  a  second  nebulosity,  we  would  not  be 
able  to  infer  anything,  except  from  the  worthless  analogy  of  a 
single  experience  ;  nor  would  we  be  able  to  infer  or  deduce,  from 
our  own,  anything,  not  already  known,  with  more  than  reasonable 
confidence.  If  we  were  still  ignorant  of  any  part  of  our  order  of 
nature,  we  should  have  no  way  to  find  out  but  the  way  we  have 
now  ;  and  while  our  confidence  in  its  stability  would  be  reasonable 
and  judicious,  it  would  not  be  necessary  or  absolute  unless  our  experi- 
mental knowledge  were  also  absolute. 

It  seems  to  me  that  the  truth  for  which  Huxley  strives,  and 
hits  with  imperfect  aim,  would  be  more  correctly  expressed  by  the 
statement  that,  if  our  knowledge  of  nature  were  to  be  made  com- 


ZOOLOGY,   AND    THE  PHILOSOPHY  OF  EVOLUTION        131 

plete,  from  beginning  to  end,  we  should  expect  to  find  that  our 
confidence  in  its  stability  had  been  reasonable,  and  judicious,  and 
wise  throughout,  and  that  any  other  expectation  would  have  been 
folly  and  suicide,  bodily  as  well  as  mental;  and  that  it  is  only  in 
this  sense  that  we  could  assert  that  it  all  lay  potentially  in  the 
cosmic  vapor. 

It  is  not  because  I  dread  or  fear  the  philosophy  of  evolution, 
that  I  refuse  to  accept  it ;  but  because  it  is  not  yet  proved.  When 
it  is  proved  I  shall  accept  it  with  cheerfulness ;  for  I  most  as- 
suredly hold  no  belief  which  is  inconsistent  with  it ;  although  I 
fail  to  see  how  the  reduction  of  all  nature  to  mechanical  princi- 
ples could  show  that  nature  is  determinate ;  for  if  exhaustive 
knowledge  of  "primitive  nebulosity"  should  sometime  show  that 
there  is  nothing  in  nature  which  might  not  have  been  expected, 
I  cannot  see  how  this  could  show  why  the  things  we  expect 
should  be  the  things  which  come  about. 

They  who  assert  that  complete  knowledge  would  be  fore- 
knowledge, forget  that,  for  minds  like  ours,  the  only  source  of 
knowledge,  either  complete  or  incomplete,  is  evidence ;  for  evi- 
dence can  tell  us  only  what  has  happened,  and  it  can  never  as- 
sure us  that  the  future  must  be  like  the  past.  Even  if  we  knew 
all  that  has  happened,  from  the  beginning  down  to  the  present 
moment,  we  should  have  to  regard  the  unknown  remainder  as 
equal,  in  all  probability,  to  the  known  past.  To  my  mind,  Jevons's 
demonstration  that,  if  certainty  be  represented  by  unity,  the  utmost 
confidence  we  can  ever  reach  by  complete  knowledge  can  never 
exceed  a  value  of  one-half,  seems  conclusive ;  but  even  if  it  be 
increased  until  it  differ  from  certainty  by  less  than  any  assignable 
quantity,  it  must  still  remain  nothing  but  reasonable  confidence. 

There  may  be  some  unknown  reason  why  the  stone  which  I 
set  free  from  my  hand  must  fall,  and  it  may  be  that,  as  my  mind 
has  been  shaped  by  natural  selection,  I  am  unable  to  expect  any- 
thing else  than  that  it  shall  fall ;  but  science  affords  no  evidence 
that  its  fall  is  necessary  or  predetermined;  for  most  thoughtful 
students  assure  us  that  the  inductive  study  of  nature  tells  us 
nothing  about  it,  except  that,  so  far  as  we  know,  all  stones,  so 
placed,  have  fallen  according  to  Newton's  laws,  and  that  we  have 
not  the  smallest  reason  to    expect    that  any  stone,  so    placed,  will 


132  .  THE  FOUNDATIONS  OF  ZOOLOGY 

act  differently ;  nor,  so  far  as  I  can  see,  would  proof  that  all 
nature  is  mechanical,  from  beginning  to  end,  be  inconsistent  with 
belief  that  everything  in  nature  is  immediately  sustained  by  Provi- 
dence; nor  am  I  able  to  see  how  it  would  be  inconsistent  with  my 
conviction  that  my  volition  counts  for  something  as  a  conditioa 
of  the  course  of  events. 

I  have  tried  to  show,  page  59,  that,  while  the  responsive 
activities  of  living  things  do  not  take  place  unless  they  are  called 
forth  by  a  stimulus,  the  things  which  they  do  under  a  stimulus- 
are  no  more  than  their  organic  mechanism  would  lead  one  to 
expect;  and  that  there  is  no  necessary  antagonism  between  those 
who  attribute  the  development  of  the  germ  to  mechanical  con- 
ditions and  those  who  attribute  it  to  the  inherent  potency  of  the 
germ  itself. 

I  have  also  tried  to  show,  page  70,  that  there  need  be  no- 
more  antagonism  between  those  who  attribute  knowledge  to  expe- 
rience and  those  who  attribute  it  to  our  innate  reason ;  for,  while 
knowledge  does  not  arise  in  our  minds  without  a  sensible  occasion, 
the  knowledge  which  does  thus  arise  may  be  no  more  than  one  who- 
knew  the  whole  natural  history  of  our  minds  might  have  expected. 

We  must  now  ask  whether  proof  that  all  nature  was  latent  in 
the  cosmic  vapor  would  be  inconsistent  with  belief  that  every- 
thing in  nature  is  immediately  intended  rather  than  predeter- 
mined. 

Certain  monists  tell  us  that  the  scientific  doctrine  of  evolution 
is  the  same  as  Pantheism,  for  "  since  the  simpler  occurrences  of 
inorganic  nature  and  the  more  complicated  phenomena  of  organic 
life  are  alike  reducible  to  the  same  natural  forces,  and  since, 
furthermore,  these  in  their  turn  have  their  common  foundation  in 
a  simple  primal  principle  pervading  infinite  space,  we  can  regard 
this  last  [the  cosmic  ether]  as  all-comprehending  divinity,  and 
upon  this  found  the  thesis  :  Belief  in  God  is  reconcilable  with 
science."  ^ 

They  who  agree  with  Haeckel  may  worship  stones,  if  they  see 
fit;  but  they  seem  to  me  to  fail  as  completely  as  any  South  Sea 
islander  to  understand  the  nature  of  scientific  evidence  ;  for  it  is 
one  thing  to  find  sermons  in   stones,  and  quite  another   to    see  a 

1  Haeckel,  "Monism." 


ZOOLOGY,  AND   THE  PHILOSOPHY  OF  EVOLUTION        1 33 

divinity  in  the  stone  itself;  "which,  if  with  reason  we  may  do, 
then  let  our  hammers  rise  up  and  boast  they  have  built  our 
houses,  and  our  pens  receive  the  honour  of  our  writings."  ^  But 
everything  must  be  determinate,  says  the  pious  evolutionist,  or 
what  would  become  of  the  fixed  order  of  nature  ?  Among  the 
things  that  occupy  the  biologist  are  such  aspects  of  nature  as  life, 
and  consciousness,  and  volition,  and  reason,  and  right  and  wrong. 
Whatever  these  things  mean,  they  are  part  of  nature,  and  the 
zoologist  cannot  push  them  out  of  sight,  if  others  may.  He  does 
not  know  what  their  places  in  the  system  of  nature  are,  but  he 
would  like  to  find  out;  and  he  knows  no  way  to  find  out  except 
to  discover. 

When  they  who  worship  at  the  shrine  of  evolution  tell  him 
there  can  be  no  spontaneity  in  nature,  because  the  order  of  nature 
is  fixed  and  unchangeable,  he  asks  what  reason  there  is  for  think- 
ing that  proof  that  everything  in  nature  is  mechanical,  and  no 
more  than  might  have  been  expected,  would  show  that  anything 
is  fixed,  or  predetermined,  or  necessary. 

Science  has  nothing  to  do  with  the  notion  of  "necessity,"  and 
is  quite  content  to  leave  it  in  the  hands  of  its  originators,  the 
metaphysicians  and  theologians  and  "philosophers,"  who  alone  are 
responsible  for  all  the  mental  confusion  it  has  brought  about. 

What  the  man  of  science  asserts  is  that  he  will  not  admit 
that  anything  is  "arbitrary."  "It  was  the  ignorance  of  man's 
reason  that  begat  this  very  name,  and  by  a  careless  term  mis- 
called the  Providence  of  God ;  for  there  is  no  liberty  for  causes 
to  operate  in  a  loose  and  straggling  way."  ^ 

Belief  that  everything  in  nature  is  mechanical  is  neither  more 
nor  less  than  belief  that  everything  in  nature  is  orderly  and  what 
might  have  been  expected ;  and  if  any  one  thinks  that  discovery 
that  things  do  take  place  in  order  is  any  reason  why  they  should, 
his  distrust  of  science  is  only  reasonable ;  for  science  is  not  for 
such  minds  as  his. 

It  is  in  my  mind  to  ask  a  question.  Will  any  amount  of 
knowledge  of  matter  and  motion  tell  the  evolutionist  whether  I 
shall  ask  it,  or  pass  it  by  and  go  on  to  another  subject .-'  If  he 
answer   Yes,    I   ask   my   question :    How   does   he   know }      If   he 

1  "  Religio  Medici." 


134  •  THE  FOUXDATIONS   OF  ZOOLOGY 

assure  me  that  a  being  so  reasonable  as  I  am  known  to  be  will 
not  ask  anything  that  might  not  have  been  expected,  I  thank  him 
for  the  compliment ;  for  I  try  to  be  a  reasonable  creature.  But  if 
he  assert  that  his  confidence  in  my  thoughts  and  actions  proves 
that  they  are  necessary,  I  must  ask  him  how  he  knows ;  for  I  fail 
to  see  how  proof  that  an  event  is  mechanical  and  neither  less  nor 
more  than  might  have  been  expected,  shows  that  it  is  necessary ; 
nor  can  I  see  any  more  reason  why  my  confidence  in  my  free- 
dom proves  that  my  acts  are  arbitrary. 

The  man  of  science  quarrels  with  no  man's  opinions ;  but  he 
will  not  be  held  responsible  for  perplexities  which  are  none  of  his 
making. 

I  am  unable  to  share  the  dread  of  the  evolutionist  that  the 
basis  of  science  may  be  destroyed  if  we  do  not  admit  that  all 
nature  must  be  determinate.  All  agree  that  the  past  is  determi- 
nate, so  far  as  the  word  means  anything  to  us,  and  there  seems 
to  be  valid  ground  for  the  belief  that  every  part  of  the  material 
universe  contains  a  permanent  record  of  every  change  which  has 
ever  occurred  in  any  part. 

"If  on  a  cold  polished  metal,  as  a  new  razor,  any  object,  such 
as  a  wafer,  be  laid,  and  the  metal  be  breathed  upon,  and,  when 
the  moisture  has  had  time  to  disappear,  the  wafer  be  thrown  off, 
though  now  the  most  critical  inspection  of  the  polished  surface 
can  discern  no  trace  of  any  form,  if  we  breathe  once  more  upon  it, 
a  spectral  image  of  the  wafer  comes  plainly  into  view ;  and  this 
may  be  done  again  and  again.  Nay,  more,  if  the  polished  metal 
be  carefully  put  aside,  where  nothing  can  deteriorate  its  surface, 
and  be  kept  so  for  many  months,  on  breathing  upon  it  again,  the 
shadowy  form  emerges.  A  shadow  never  falls  upon  a  wall  with- 
out leaving  thereupon  a  permanent  trace,  a  trace  which  might  be 
made  visible  by  resorting  to  proper  processes.  Upon  the  walls  of 
our  most  private  apartments,  where  we  think  the  eye  of  intrusion 
is  altogether  shut  out,  and  our  retirement  can  never  be  profaned, 
there  exist  the  vestiges  of  all  our  acts."  ^ 

Babbage  has  pointed  out  ("Ninth  Bridgewater  Treatise"  pp. 
1 1 3-1 1 5)  "that  if  we  had  power  to  follow  and  detect  the  minutest 
effects  of  any  disturbance,  each  particle  of  existing  matter  would  fur- 

1  Draper,  "  Conflict  of  Science  and  Religion." 


ZOOLOGV,   AND    THE  PHILOSOPHY  OF  EVOLUTION        135 

nish  a  register  of  all  that  has  happened.  The  track  of  every  canoe, 
of  every  vessel  that  has  as  yet  disturbed  the  surface  of  the  ocean, 
whether  impelled  by  manual  force  or  elemental  power,  remains 
forever  registered  in  the  future  movement  of  all  succeeding  particles 
which  may  occupy  its  place.  The  furrow  which  it  left  is  indeed 
instantly  filled  up  by  the  closing  waters,  but  they  draw  after  them 
other  and  larger  portions  of  the  surrounding  element,  and  these 
again,  once  moved,  communicate  motion  to  others  in  endless  suc- 
cession. The  air  itself  is  one  vast  library,  in  whose  pages  are 
forever  written  all  that  man  has  said  or  even  whispered.  There, 
in  their  mutable  but  unerring  characters,  mixed  with  the  earliest 
as  well  as  the  latest  sighs  of  mortality,  stand  forever  recorded 
vows  unredeemed,  promises  unfulfilled,  perpetuating  in  the  united 
movements  of  each  particle  the  testimony  of  man's  changeful  will."^ 

So  far  as  we  know,  nothing  that  has  ever  been  can  be  as  if  it  had 
not  been  ;  and  we  seem  to  have  good  ground  for  believing  that  every 
portion  of  the  material  universe  contains  a  record  of  every  change 
that  has  taken  place  in  all  its  parts,  and  also  for  believing  that  there 
is  no  limit  to  the  power  of  minds  like  ours  to  read  and  interpret 
this  record.  Every  new  experience  also  shows  that  our  expectation 
that  the  future  will,  on  the  whole,  be  like  the  past  is  reasonable.  In 
these  facts  science  finds  a  basis  broad  enough  and  firm  enough 
for  all  our  needs ;  for  to  this  extent  the  data  of  science  are  latent 
in  the  physical  universe,  even  if  the  future  is,  in  part,  to  be  what 
man  and  other  living  things  make  it. 

If  these  evolutionists  who  hold  that  all  nature  is  determinate  and 
necessary  are  right,  mind  would  seem  to  be  useless.  It  may,  for 
all  I  know  to  the  contrary,  be  true  that,  when  I  perform  an  action 
because  my  reason  approves  it,  neither  the  performance  of  the 
action  nor  the  approval  of  my  reason  is  anything  more  than  exhaust- 
ive knowledge  of  the  mechanism  of  my  brain  might  have  led  one 
to  expect ;  and  if  it  follows  that  my  action  is  necessary,  and  must 
take  place,  whether  my  reason  approve  it  or  not,  reason  would  seem 
to  be  useless ;  but  I  cannot  see  why  this  should  follow,  for  I  fail 
to  see  how  or  why  proof  that  my  reason  is  mechanical  and  no 
more  than  might  have  been  expected  from  my  structure  should 
be  inconsistent  with  my  confidence  in  its  value,  since  I  cannot  con- 

1  Quoted  by  Jevons,  "  Principles  of  Science,"  p.  758. 


136  THE  FOUNDATIONS  OF  ZOOLOGY 

ceive  how  this  proof  could  show  that  it  is  necessary,  or  predetermined, 
or  useless. 

I  know  the  value  of  my  reason  by  what  seems  to  me  the  best 
of  all  evidence.  If  it  were  proved  useless,  I  should  be  quite  ready 
to  believe;  but  the  improbability  of  this  opinion  seems  to  me  so 
much  like  impossibility,  that  I  must  ask  for  proof  which  is  corre- 
spondingly conclusive ;  for  I  most  assuredly  refuse  to  give  any 
weight  to  the  "faith"  of  pious  evolutionists,  and  I  must  insist  on 
my  right  to  demand  more  evidence  if  more  is  to  be  had,  for  I 
cannot  accept  the  mind  of  the  evolutionist  as  a  measure  of  nature. 

Living  things  are  continually  bringing  about  rearrangements  of 
matter  and  motion  which  would  never,  so  far  as  I  can  see,  have 
come  about  without  them,  and  many  of  the  things  which  they  thus 
bring  about  are  useful  to  the  beings  which  bring  them  about.  The 
earth  would  be  very  different  in  many  respects  if  man  had  never 
inhabited  it,  and  the  effects  of  his  activity  will  last  as  long  as  matter, 
whatever  may  be  his  fate.  His  influence  upon  the  earth  would 
have  been  very  different  if  the  plants  of  Carboniferous  times  had 
not  stored  up  solar  energy  and  worked  their  changes  in  matter 
millions  of  years  ago.  If  the  dodo,  and  the  great  auk,  and  the 
halicore,  and  the  American  bison  could  tell  their  story,  they  would 
bear  witness  that  man  is  a  factor  in  the  order  of  nature. 

They  who  are  discontented  with  reasonable  or  "moral"  certainty, 
and  tell  us  they  want  absolute  certainty,  must  find  this  sort  of  certainty 
if  they  can  and  where  they  can,  but  their  words  seem  strange  to 
the  zoologist.  He  knows  that  the  rocks  are  full  of  the  remains  of 
organisms  which  passed  out  of  existence  because  they  were  born 
in  evil  times,  when  the  adjustments  to  the  order  of  nature,  which 
had  served  the  purposes  of  their  ancestors  for  millions  of  years, 
ceased  to  hold  good. 

If  our  race  should  ever  find  itself  where  the  old  order  changes ; 
if  our  reasonable  expectations  should  disappoint  us;  if  what  we 
call  the  "  order  "  of  nature  should  prove  to  be  no  more  than  natural 
selection  would  lead  us  to  expect ;  and  if  a  different  selective 
standard  should  some  time  modify  this  order,  —  every  zoologist  knows 
that  the  human  species  would  not  be  the  first  to  meet  this  evil  fate. 

If,  with  Aristotle,  we  believe  "  that  is  natural  which  holds 
good " ;    if,  with    Erigena,  we   hold  that  nature  is  the  sum  of    all 


ZOOLOGY,  AND   THE  PHILOSOPHY  OF  EVOLUTION        1 37 

things,  —  we  cannot  believe  that  life  and  consciousness  and  reason 
and  volition  are  anything  but  part  of  nature.  The  question  the 
zoologist  would  like  to  answer  is,  what  their  place  in  nature  is. 
So  far  as  I  am  aware,  no  one  believes  that  these  aspects  of  nature 
exist  in  themselves,  without  antecedents,  for  we  know  that  many 
of  their  antecedents  are  physical,  and  we  want  to  find  out,  if  we 
can,  whether  this  is  true  of  all  of  them  or  not.  For  my  own  part, 
I  fail  to  see  what  bearing  this  wish  has  on  the  question  whether 
the  order  of  nature  is  "  fixed "  or  unfixed ;  nor  can  I  see  how 
proof  that  the  conditions  which,  being  given,  are  good  reasons 
for  expecting  reason  or  the  moral  sense,  are  mechanical,  should 
show  that  reason  and  morality  are  useless. 

They  who  take  refuge  in  an  imponderable  ether  as  soon  as 
they  find  it  difficult  to  discover,  in  ponderable  matter,  the  key  to 
all  the  antecedents  to  certain  phenomena  of  light  and  electricity, 
have  no  reason  to  cry  out  that  the  fixed  order  of  nature  is  threat- 
ened, because  the  modest  zo5logist  has  not  yet  been  able  to  find, 
in  ponderable  matter  and  physical  energy,  the  key  to  all  his 
problems. 

Berkeley  tells  us  that  human  knowledge  has  its  basis  in  experi- 
ence, and  that  its  scientific  value  is  to  be  measured  by  the  amount 
of  this  experience ;  and  Huxley  assures  us  that  there  is  but  one 
kind  of  knowledge  and  but  one  way  to  acquire  it.  They  hold  our 
practical  test  of  truth  to  be  evidence,  although  a  pious  evolutionist, 
who  admits  that,  for  all  he  knows,  they  may  be  right,  is  a  heretic ; 
for  Herbert  .Spencer  tells  him  that  the  Philosophy  of  Evolution 
stands  or  falls  with  the  assertion  that  the  ultimate  criterion  of  truth 
is  inability  to  conceive  its  negative. 

If  you  will  read  Part  VH.  of  his  "  Principles  of  Psychology"  with 
care,  you  will  note  that  its  author  tells  us  that,  unless  we  admit 
this,  we  cannot  be  his  disciples.  It  is  not  enough  to  admit  igno- 
rance of  things  ultimate,  or  to  confess  that,  for  all  one  knows,  in- 
ability to  conceive  its  negative  may  sometime  prove  to  be  the 
ultimate  criterion  of  truth.  One  may  admit  that  he  is  unable  to 
discover  any  line  which  separates  the  responsive  actions  of  living 
things  in  general  from  the  rational  actions  of  thinking  men ;  that 
he  does  not  know  how  or  where  instinct  and  impulse  and  emotion 
give  place  to  reason.     One  may  have  as  little  faith  in  the  idealism  of 


138  THE  FOUNDATIONS   OF  ZOOLOGY 

Berkeley  as  he  has  in  Spencer's  realism,  or  in  the  materialism  of 
German  physics,  or  in  the  monism  of  the  psychologists ;  but  unless 
he  knows  what  the  relation  between  mind  and  matter  is,  he  can- 
not join  the  throng  of  worshippers  before  the  shrine  of  this  modern 
idol  of  the  theatre;  for  its  leader  tells  him  that  suspension  of  judg- 
ment on  this  difficult  question  is  as  fatal  as  disbelief. 

Proof  that  we  should  not  be  here  if  our  remote  ancestors  had 
not  responded  to  the  order  of  nature  as  they  did  is  no  proof  that 
our  minds  are  a  measure  of  nature,  or  that  our  responses  will  be 
valuable  in  the  future,  or  that  nature  is  determinate. 

Now  the  difference  between  belief  that  the  ultimate  test  of 
truth  is  the  inconceivability  of  its  negative,  and  belief  that  our 
practical  test  of  truth  is  evidence,  is  this :  that  while  inability  to 
conceive  the  negative  of  a  proposition  may  be  absolute  to  us,  as 
nature  has  made  us,  at  our  present  intellectual  level,  evidence  is 
progressive,  and  can  afford  no  basis  for  ultimate  philosophy. 

Our  pre-Cambrian  ancestors  may  have  been  unable  to  conceive 
the  negative  of  many  propositions ;  but  what  does  the  inability  of 
a  turnip  or  a  sponge  to  conceive  the  negative  of  Newton's  laws 
signify }  Or  what  would  our  own  inability  signify  if  we  should 
sometime  find  out  that  the  ponderable  matter  which  makes  up 
what  we  call  "our  universe"  has  been  sifted  out  or  segregated 
from  other  forms  of  matter,  by  its  property  of  weight }  For  no 
less  distinguished  an  authority  than  Herschel  held  that  there  is 
proof  of  the  existence  of  levitative  matter  as  well  as  gravitative 
matter. 

One  volume  of  Herbert  Spencer's  "  Philosophy "  is  devoted  to 
proof  that  we  primarily  know  objects;  but  to  this  long  argument 
Berkeley  answers :  Granted.  Most  assuredly  we  primarily  know 
objects ;  but  he  tells  us  that  the  objects  we  know  primarily  are 
objects  of  sense. 

So  the  frozen  river  of  philosophy  grinds  on,  scratching  the 
surface  of  the  everlasting  hills,  and  melting  before  the  genial  sun- 
shine of  science,  only  to  receive  new  accretions  from  the  unknown 
and  frozen  space  beyond  the  snow-line. 

Some  fifteen  hundred  years  have  passed  since  we  were  told 
by  Procles  that  "  there  are  two  sorts  of  philosophers.  The  one 
placed  Body  first  in  the  order  of  beings,  and  made  the  faculty  of 


ZOOLOGY,  AND  THE  PHILOSOPHY  OF  EVOLUTION-        1 39 

thinking  depend  thereupon,  supposing  that  the  principles  of  all 
things  are  corporeal ;  that  Body  must  really  or  principally  exist, 
and  all  other  things  in  a  secondary  sense,  and  by  virtue  of  that. 
Others,  making  all  corporeal  things  to  be  dependent  upon  Soul  or 
Mind,  think  this  to  exist  in  the  first  place  and  primary  sense,  and 
the  being  of  Bodies  to  be  entirely  derived  from,  and  to  presuppose 
that  of  Mind."i 

While  the  modern  psychologist  tells  us  that  there  is  a  third 
point  of  view,  and  that,  for  all  we  know  to  the  contrary,  both 
mind  and  matter  may  ultimately  prove  to  be  phenomenal ;  that  all 
mind  may  be  matter  in  motion,  and  all  matter  in  motion  mind,  or 
at  least  the  raw  material  of  mind,  I  cannot  see  why  the  admis- 
sion of  this  possibility  compels  us  to  take  a  side  and  make  a 
choice ;  for  may  we  not  find  a  fourth  alternative,  in  a  humble 
confession  that,  while  we  do  not  know  what  the  relation  between 
mind  and  matter  is,  we  wish  to  find  out  ?  "  And,  although  it  may, 
perhaps,  seem  an  uneasy  reflection  to  some  that,  when  they  have 
taken  a  circuit  through  so  many  refined  and  unvulgar  notions,  they 
should  at  last  come  to  think  like  other  men ;  yet,  methinks,  this 
return  to  the  simple  dictates  of  nature,  after  having  wandered 
through  the  wild  mazes  of  philosophy,  is  not  unpleasant.  It  is 
like  coming  home  from  a  long  voyage :  a  man  reflects  with  pleas- 
ure on  the  many  difificulties  and  perplexities  he  has  passed 
through,  sets  his  heart  at  ease,  and  enjoys  himself  with  more  satis- 
faction for  the  future."  2 

If  the  antecedents  to  consciousness  are  outside  consciousness, 
it  seems  no  more  than  natural  that  we  should  be  unconscious  of 
them ;  and  the  zoologist  who  admits  that  he  does  not  know  whether 
they  are  or  are  not  all  to  be  found  in  that  part  of  the  universe 
which  may  be  made  manifest  to  sense,  does  not  feel  guilty  of  a 
threat  to  the  fixed  order  of  nature,  or  to  anything  or  anybody  else. 

There  are  two  reasons  why  biology  and  the  "  Philosophy  of 
Evolution  "  should  be  associated. 

In  the  first  place,  there  is  a  wonderful  analogy  between  the 
problems  of  the  sensible  universe  and  the  unfolding  of  the  latency 
of  the  germ  into  the  potency  of  the  fully  developed  living  being. 

1  Berkeley,  "  Siris,"  p.  263. 

2  Berkeley,  Preface  to  "  The  Three  Dialogues." 


I40  THE  FOUNDATIONS  OF  ZOOLOGY 

It  is  not  impossible  that  the  key  to  the  more  specific  problem  may- 
fit  the  lock  which  seals  the  greater. 

In  the  second  place,  the  two  subjects  are  historically  associ- 
ated. So  long  as  men  believed  that  species  are  distinct  creations, 
no  philosophy  of  evolution  could  have  gained  general  acceptance. 
By  convincing  all  thoughtful  persons  that  species  have  a  history 
which  may  be  studied  by  scientific  methods,  Darwin  led  many  who 
would  not  otherwise  have  given  it  a  hearing,  to  treat  the  new 
philosophy  with  respect :  but  natural  science  is  not  "  philosophy," 
notwithstanding  this  intimate  historical  connection  between  the 
proof  that  species  are  mutable  and  the  spread  of  belief  in  the 
"  Philosophy  of  Evolution."  I  have  selected  the  passage  which 
I  have  put  at  the  head  of  this  chapter  in  order  to  show  that  the 
view  of  the  matter  which  is  here  set  forth  is  not  new,  even  among 
advanced  biologists. 

Huxley's  attitude  will,  no  doubt,  be  a  surprise  to  many  who 
think  they  have  read  his  books  with  diligence.  He  continually 
calls  himself  an  "  Evolutionist,"  and  he  can  hardly  blame  a  reader 
who,  failing  to  draw  nice  distinctions,  holds  him  to  be  one  of  the 
chief  pillars  in  the  temple  of  the  new  philosophy.  Some  confu- 
sion may  be  permitted  to  those  who  remember  his  public  lectures 
on  "  Evolution,"  his  essays  with  the  same  title,  and  his  declaration 
that  the  work  of  his  life  has  involved  him  "  in  an  endless  series 
of  battles  and  skirmishes  over  evolution." 

It  is  easy  for  one  who  understands  his  true  position  to  see 
that  his  essays  lend  no  countenance  to  the  opinion  that  he  has 
ever  been  or  sought  to  be  either  a  pillar  or  a  disciple  of  any 
system  of  philosophy ;  for  he  has  never  ceased  from  affirming  his 
ignorance  of  many  of  the  subjects  which  philosophy  seeks  to 
handle. 

His  evolution  is  not  a  system  of  philosophy,  but  part  of  the 
system  of  science.  It  deals  with  history  —  with  the  phenomenal 
world  —  and  not  with  the  question  what  may  or  may  not  lie 
behind  it. 

During  the  last  half-century  natural  science  has  become  his- 
torical. We  have  opened  and  learned  to  read  a  new  chapter  in 
the  records  of  the  past.  The  attributes  of  living  things,  which 
seemed  to  the  older  naturalists   to  be    complete   and   independent 


ZOOLOGY,   AND    THE  PHILOSOPHY  OF  EVOLUTION        I4I 

in  themselves,  have  proved  to  have  a  history  which  can  be  studied 
by  the  methods  of  science.  They  have  been  found  to  be  steps  in  a 
long  sequence  of  events  as  orderly  and  discoverable  as  the  events 
which  are  studied  by  the  astronomer  or  the  geologist. 

The  cultivation  of  natural  science  in  this  historical  field,  and 
the  discovery  that  the  present  order  of  living  things,  including 
conscious,  thinking,  ethical  man,  has  followed  after  an  older  and 
simpler  state  of  nature,  is  not  "  philosophy,"  but  science.  It 
involves  no  more  belief  in  the  teachings  of  any  system  of  phi- 
losophy than  does  the  knowledge  that  we  are  the  children  of  our 
parents  and  the  parents  of  our  children;  but  it  is  what  Huxley 
means  by  "evolution."  ^ 

His  lectures  on  "  Evolution "  deal  with  paleontology,  and 
narrate  facts  which  are  found  in  every  text-book  on  the  subject; 
but  natural  science,  as  it  is  taught  in  the  text-books  on  botany 
and  zoology  and  embryology  and  paleontology,  is,  most  assuredly, 
no  "  Philosophy  of  Evolution."  It  fell  to  Huxley  to  fight  and 
win  a  battle  for  science ;  and  while  he  himself  calls  it  a  battle 
for  evolution,  his  use  of  the  word  need  mislead  none,  although  it 
has  misled  many. 

One  word  in  its  time  plays  many  parts,  and  the  word  "  evo- 
lution "  has  had  many  meanings.  To-day,  in  popular  estimation, 
an  evolutionist  is  not  a  follower  of  Bonnet ;  nor  one  who  is  occu- 
pied with  the  binomial  theorem,  or  with  the  evolutions  of  fleets 
and  armies.  Neither  is  he  a  cultivator  of  natural  science'.  What- 
ever the  word  may  have  meant  in  the  past,  it  has,  in  common 
speech,  come  to  mean  a  believer  in  that  philosophy  of  evolution 
which,  according  to  such  evolutionists  as  Huxley,  is  "  premature." 
Since  this  is  so,  and  since  the  growth  of  language  is  beyond  in- 
dividual control,  would  it  not  be  well  for  those  who  stand  where 
Huxley  stands,  and  "  have  nothing  to  say  to  any  philosophy  of 
evolution,"  to  stop  calling  themselves  "Evolutionists,"  and  to  be 
content  with  the  good  old  name  of  "  Naturalist "  ? 

To  the  pious  evolutionist,  who  asks  what  will  become  of  the 
fixed  order  of  nature  if  we  are  not  convinced  that  everything  is 
determinate,  we  answer  that,  while  this  sort  of  reasoning  is  not 
new,  it  has  a  strange  sound  in  the  mouth  of  a  student  of  science. 

1  See  Huxley,  "  Essays,"  V.  i.,  pp.  44-54- 


142  THE  FOUNDATION'S   OF  ZOOLOGY 

The  order  of  nature  has  outlasted  many  systems  of  philosophy, 
and  it  may  survive  others.  We  have  found  our  astronomy  and 
our  geology  and  our  law  of  the  mutability  of  species,  and  none 
of  the  dreadful  things  predicted  by  "philosophers"  have  come 
about.  There  may  still  be  more  things  in  heaven  and  earth  than 
are  dreamed  of  in  "philosophy." 

History  warns  us  that,  as  the  price  of  progress  in  science, 
all  the  idols  of  the  theatre,  and  all  other  idols,  "must  be  abjured 
and  renounced  with  firm  and  solemn  resolution,  and  the  under- 
standing must  be  completely  freed  and  cleared  of  them;  so  that 
the  access  to  the  kingdom  of  man,  which  is  founded  on  the 
sciences,  may  resemble  that  to  the  kingdom  of  heaven,  where  no 
admission  is  conceded  except  to  children." 

If  the  world  thinks  hard  names  are  the  just  due  of  them  who 
assert  their  living  wish  to  know,  while  humbly  confessing  igno- 
rance, the  biologist  must  bear  up  as  well  as  he  can  if  he  is  called 
a  "scientific  Rip  Van  Winkle,"  or  an  "agnostic,"  or  even  "a  malig- 
nant and  a  turban'd  Turk." 

If  we  seek  admission  to  the  temple  of  natural  knowledge 
naked  and  not  ashamed,  like  little  children,  hard  names  cannot 
hurt  us,  nor  need  they  scare  us. 


LECTURE    VI  — Part  II 

A  NOTE  ON  THE  VIEWS   OF  GALTON   AND   WEISMANN  ON 

INHERITANCE 

Two  of  the  most  prominent  writers  on  inheritance,  Weismann 
and  Galton,  base  their  views  of  variation  on  the  assumption  that 
at  each  remote  generation,  the  ancestors  of  a  modern  organism 
were  innumerable,  although  a  little  reflection  will  show  that  this 
assumption  is  quite  untenable. 

Weismann,  in  his  earlier  writings  at  least,  finds  the  "cause  of 
variation  "  in  the  recombination,  by  sexual  reproduction,  of  the 
effects  of  the  diversified  influences  which  acted  upon  the  innumer- 
able protozoic  ancestors  of  each  modern  metazoon ;  but  this 
opinion  deserves  little  consideration,  as  a  contribution  to  our 
knowledge  of  inheritance,  if  we  can  prove  that  these  protozoic 
ancestors  must  have  been  very  few,  and  if  we  can  also  prove  that, 
if  these  few  were  ancestors  of  any  modern  metazoon,  they  must 
have  been  the  common  ancestors  of  all  the  modern  metazoa. 

Galton's  view  of  the  diversity  among  individuals  is  much  like 
Weismann's.  He  says  :  "  It  is  not  possible  that  more  than  one- 
half  of  the  varieties  and  number  of  the  parental  elements,  latent 
or  potential,  can  on  the  average  subsist  in  the  offspring.  For  if 
every  variety  contributed  its  representatives,  each  child  would  on 
the  average  contain,  actually  or  potentially,  twice  the  variety  and 
twice  the  number  of  elements,  whatever  they  may  be,  that  were 
possessed  at  the  same  stage  of  its  life  by  either  of  its  parents, 
four  times  as  many  as  any  of  its  grandparents,  1024  times  as 
many  as  any  of  its  ancestors  of  the  tenth  degree,  and  so  on." 

As  he  holds  that  each  offspring  must  therefore  get  rid,  in 
some  way,  of  half  the  variety  transmitted  from  its  ancestors,  he 
finds  an  explanation  of  the  diversity  between  individuals  in  the 
diversity  of  the  retained  halves  of  their  variety. 

143 


144  THE  FOUNDATIONS  OF  ZOOLOGY 

Each  person  has  two  parents,  and  four  grandparents ;  but 
even  in  a  country  like  ours,  which  draws  its  people  from  all 
quarters  of  the  earth,  each  of  the  eight  great-grandparents  is  not 
always  a  distinct  person ;  for  when  the  parents  are  cousins,  this 
number  is  six,  or  five,  or  even  four,  instead  of  eight.  Among 
more  primitive  folks,  who  stay  at  home  generation  after  genera- 
tion, and  marry  neighbors,  a  person  whose  ancestors  have  trans- 
gressed none  of  our  social  laws  may  have  a  minimum  ancestry 
of  only  four  in  each  generation.  The  maximum  and  the  mini- 
mum fixed  by  our  customs  are  given,  for  ten  generations,  in  the 
two  lines  below:  — 

2  —  4—8  —  16  —  32  —  64  —  128  —  256  —  512  —  1024    .    .    .    2046 
2-4-4-4-4-4-     4-     4-     4-       4    •     .     .        38 

Few  persons  who  can  trace  their  ancestry  for  ten  generations 
with  completeness  are  descended  from  1024  distinct  persons  in 
the  tenth  generation;  and  in  all  old  stable  communities  of  simple 
folks  the  number  is  very  much  smaller.  In  the  long  run,  the 
number  of  ancestors  in  each  generation  is  determined  by  the 
average  sexual  environment,  and  it  must  be  a  small  and  pretty 
constant  number. 

All  genealogical  study  gives  indirect  evidence  of  this  familiar 
fact,  which  has  not  been  adequately  recognized  by  students  of  in- 
heritance. I  have  made  a  computation  from  the  genealogical  his- 
tory of  the  people  of  a  small  island  on  our  coast.  These  people 
lead  a  simple  life,  or  at  least  they  have  done  so  in  the  past ;  but 
most  of  the  men  have  been  sailors,  and  have  ranged  much  farther 
in  search  of  mates  than  agricultural  people.  I  have  selected  three 
persons  whose  ancestry  is  recorded  in  detail  for  some  seven  or 
eight  generations.  These  three  persons  would  not  be  popularly 
regarded  as  near  relations,  for  they  have  no  parents  or  grand- 
parents with  like  names,  although  two  of  the  grandparents  were 
cousins.  The  generations  are  not  quite  parallel,  for  the  period 
covered  by  eight  in  one  line  is  covered  by  seven  in  the  two  others, 
and  the  average  is  about  seven  and  a  half. 

In  seven  and  a  half  generations  the  maximum  ancestry  for  one 
person  is  382,  or,  for  three  persons,  1146.  The  names  of  452  of 
them,  or  nearly  half,  are  recorded,  and  these  452  named  ancestors 


VJEIVS   OF  G ALTON  AND    WEISMANN  ON  INHERITANCE     1 45 

are  not  452  distinct  persons,  but  only  149;  many  of  them,  in  the 
more  remote  generations,  being  common  ancestors  of  all  three  in 
many  lines.  If  the  lines  of  descent  from  the  unrecorded  ancestors 
were  interrelated  in  the  same  way,  as  they  would  surely  be  in  an 
old  and  stable  community,  the  total  ancestry  of  these  three  per- 
sons, for  seven  and  a  half  generations,  would  be  378  persons  in- 
stead of   1 146. 

Few  of  us  know  even  the  names  of  all  the  living  descendants 
of  each  of  our  sixty-four  ancestors  of  the  sixth  generation ;  and,  so 
far  as  our  own  choice  is  concerned,  marriage  with  one  of  them 
may  be  an  accident ;  for  the  probability  of  such  a  marriage  de- 
pends upon  things  which  are  in  great  part  independent  of  us, 
upon  the  size  of  the  circle  of  acquaintances,  and  the  distance 
of  the  places  to  which  ancestors  wandered.  For  if  each  pair  of 
ancestors  had  only  four '  children,  more  than  twelve  thousand  of 
their  descendants  may  now  be  living  (4048  +  8096). 

If  a  city  like  Baltimore,  where  the  strangers  to  each  one  of  us 
outnumber  our  acquaintances  a  thousand  fold,  could  be  quaran- 
tined against  people  from  outside  for  a  thousand  years,  each  suc- 
cessive generation  would  be  much  like  the  present,  so  far  as  known 
relationships  are  concerned,  although,  at  the  end  of  this  period, 
the  inhabitants  would  not  be  descended  from  the  Baltimoreans  of 
our  day,  but  from  only  a  very  few  of  them.  Most  of  our  lines 
would  be  extinct;  and  the  few  that  survived  would  include  most 
of  the  Baltimoreans  of  the  year  2898. 

All  this  is  proved,  indirectly  but  conclusively,  by  genealogical 
statistics ;  and  while  a  thousand  years  are  but  as  yesterday  in  the 
history  of  species,  zoological  phenomena  furnish  evidence  that 
allied  animals  must  be  related  to  each  other,  at  two  widely  sepa- 
rated generations,  like  these  successive  generations  of  Baltimoreans. 

Of  all  the  individual  animals  which  make  up  the  species  at  a 
given  period,  very  few  will  have  descendants  at  a  later  period,  and 
these  few  will  be  the  common  ancestors  of  all  the  individuals 
which  represent  the  stock  at  the  later  period. 

The  extinction  of  species  is  a  familiar  conception.  The  extinc- 
tion of  the  lines  of  descent  from  individuals  is  no  less  real,  and, 
in  the  study  of  inheritance,  vastly  more  important ;  for  it  is  the 
fact  of  which  the  extinction  of  species  is  only  an  expression. 


146  THE  FOUNDATIONS   OF  ZOOLOGY 

As  we  trace  back  the  ancestral  tree,  it  divides  into  two  branches 
for  the  parents,  and  again  into  four,  and  into  eight,  for  the  grand- 
parents and  great-grandparents,  and  so  on  for  a  few  generations ; 
but  a  change  soon  takes  place. 

The  student  of  family  records  may  be  permitted  to  picture 
genealogy  as  a  tree  whose  branches  become  more  and  more 
numerous  as  we  go  farther  and  farther  backwards  from  our  start- 
ing-point into  the  past ;  but  this  cannot  be  permitted  to  the 
zoologist ;  for  the  average  number  of  ancestors  in  each  generation 
cannot  be  greater  than  the  average  number  of  individuals  in  the 
average  sexual  environment.  It  may  be  very  much  less,  however, 
for  most  of  the  individuals  in  each  generation  may  fail  to  perpetu- 
ate their  lines  to  remote  posterity.  Now,  no  animal  in  a  state  of 
nature  ranges  so  far  as  man  in  search  of  a  mate ;  and  the  sexual 
environment  of  such  animals  as  the  fishes  in  a  brook  or  pond, 
or  the  parasites  in  the  intestine  of  a  mammal,  is  very  narrow,  as 
it  is  in  many  plants.  While  new  blood  no  doubt  finds  its  way  in 
from  time  to  time,  its  influence  is  more  than  balanced  by  the  ex- 
tinction of  genetic  lines.  The  series  of  ancestors  of  each  modern 
animal  is  long  beyond  measure  or  conception,  but  the  number  of 
ancestors  in  each  remote  generation  can  never  be  very  great,  though 
it  may  be  extremely  small. 

The  data  of  systematic  zoology  also  force  us  to  believe  the 
ancestry  of  all  the  individuals  of  a  species  has  been  practically 
identical,  except  for  some  slight  divergence  in  the  most  recent  part 
of  their  history. 

Instead  of  picturing  the  genealogy  of  a  species  as  a  tree,  the 
zoologist  must  picture  it  as  a  slender  thread,  of  very  few  strands, 
a  little  frayed  at  the  near  end,  but  of  immeasurable  length,  and 
so  fine  that  its  thickness  is  as  nothing  in  comparison.  The  num- 
ber of  strands  is  fixed  by,  but  is  very  much  smaller  than,  the  aver- 
age sexual  environment.  If  we  choose,  we  may  picture  a  fringe 
of  loose  ends  all  along  the  thread,  to  represent  the  ancient  animals 
which,  having  no  descendants,  are  now  as  if  they  had  never  been. 
Each  of  the  strands  at  the  near  end  is  important  as  a  possible  line 
of  union  between  the  thread  of  the  past  and  that  of  the  distant 
future. 

The    gist   of    the   whole    matter    is   this :    that   we   must    picture 


V/EIVS  OF  G ALTON  AND    WEISMANN  ON  INHERITANCE     1 47 

this  slender  thread  as  common  to  all  the  individuals  of  the  species, 
whose  divergence  from  each  other  is  infinitesimal  as  compared 
with  the  ancestry  which  they  share  in  common.  The  branches  of 
a  human  genealogical  tree  diverge  for  a  few  generations  by  geo- 
metrical progression,  but  we  soon  find  traces  of  a  change,  and  if 
the  record  were  long  enough  to  have  any  zoological  significance, 
we  should  surely  find  all  the  members  of  the  species  descended 
from  a  few  ancestors  in  each  remote  generation,  and  these  few 
the  common  ancestors  of  all.  So  too  of  the  common  ancestors  of 
divergent  species,  or  those  of  larger  groups;  if  one  metazoon  is 
descended  from  pre-Cambrian  unicellular  ancestors,  the  same  uni- 
cellular individuals  must  have  been  the  common  ancestors  of  all 
the  metazoa ;  and  we  may  be  confident  that  there  were  not  very 
many  of  them  in  any  one  generation.  It  is  quite  possible  that 
they  were  so  few  as  a  single  pair,  or  even  one. 

There  is  nothing  novel  in  all  this.  Galton  has  himself 
devoted  an  appendix  to  the  mathematical  study  of  the  extinction 
of  family  names ;  although  he,  like  other  writers  on  inheritance, 
seems  to  forget  it  when  he  assumes  that  the  remote  ancestors  of 
two  persons  were,  like  the  parents,  distinct  individuals,  and  that 
the  child  must  therefore  have  twice  as  much  ancestry  as  either 
parent,  and  consequently  twice  as  much  variety,  unless  there  is 
some  way  to  cancel  half  of  it  at  each  step. 

I  called  attention  to  the  bearing  of  this  convergence  of  ances- 
try on  the  problem  of  inheritance,  in  1883,  in  words  which  still 
seem  clear ;  although  the  views  of  both  Galton  and  Weismann  on 
variation  are  based  on  the  unfounded  assumption  that  each 
sexual  act  brings  together  two  totally  dissimilar  sets  of  factors, 
instead  of  two  factors  which  are  alike  in  innumerable  features, 
for  each  one  in  which  they  differ. 

My  statement  is  as  follows:  "In  order  to  breed  together, 
animals  must  be  closely  related ;  they  must  belong  to  the  same 
species,  or  to  two  closely  related  species.  Since  the  individuals 
which  belong  to  two  closely  related  species  are  the  descendants 
of  a  common  and  not  very  remote  ancestral  species,  it  is  clear 
that  almost  the  whole  of  their  history  has  been  shared  by  them 
in  common  ;  all  their  generic  characteristics  being  inherited  from 
this  ancestor.     Only   the   slight   differences   in   minor  points   which 


148  THE  FOUNDATIONS  OF  ZOOLOGY 

distinguish  one  species  from  another  have  been  acquired  since 
the  two  diverged,  and  not  even  all  of  these  slight  differences. 

"We  know  that  the  duration  of  even  the  most  persistent 
species  of  the  higher  animals  is  only  an  infinitesimal  part  of 
the  whole  history  of  their  evolution,  and  it  is  clear  that  the  com- 
mon characteristics  of  two  allied  species  must  outnumber,  thou- 
sands of  times,  the  differences  between  them.  It  follows  that  the 
parents  of  any  possible  hybrid  must  be  alike  in  thousands  of 
features  for  one  in  which  they  differ.  Crossing  simply  results  in 
the  formation  of  a  germ  by  the  union  of  a  male  and  a  female 
element  derived  from  two  essentially  similar  parents,  with,  at 
most,  only  a  few  secondary  and  comparatively  slight  differences, 
all  of  which  have  been  recently  acquired." 

I  trust  that  you  will  agree  with  me  that  due  consideration  of 
the  subject  which  is  here  presented  might  have  saved  much 
unprofitable  discussion  of  "  the  causes  of  variation  " ;  for  it  seems 
clear  that  we  must  seek  in  the  modern  world,  and  not  in  the 
remote  past,  for  an  explanation  of  that  diversity  among  individ- 
uals which  passes  under  the  name  of  "  variation." 

I  have  called  your  attention  to  these  facts  because  they  serve 
to  introduce,  and  to  throw  light  upon,  the  subject  of  the  next 
lecture.  The  Statistical  Study  of  Inheritance ;  although  they  seem 
to  me  to  throw  light  upon  other  zoological  problems. 

If  the  extinction  of  a  genetic  line  may  be  so  slow  that  a  fail- 
ing stock  may  go  on  from  bad  to  worse  for  many  generations 
before  it  is  utterly  destroyed,  is  it  not  clear  that  we  can  seldom 
hope  to  discover  what  determines  the  ultimate  survival  or  extinc- 
tion of  a  genetic  line.-*  Is  it  not  equally  clear  that  artificial  selec- 
tion, by  the  sudden  and  utter  destruction  of  the  discarded,  is  no 
measure  of  natural  selection  .-* 

Unless  individuals  with  the  same  useful  quality  breed  together 
it  is  hard  to  see  how  this  useful  quality  can  be  intensified  by 
natural  selection,  and  as  it  also  seems  hard  to  find  in  nature  any 
reason  why  these  individuals  should  seek  out  and  unite  with  each 
other,  this  criticism  of  natural  selection  seemed  to  Darwin  to  be  a 
real  difficulty  ;  but  we  must  remember  that  while  the  sexual  union 
of  those  individual  animals  whose  descendants  would  be  the  fit- 
test   to    survive    may    b2    rare    and    exceptional,  the  survival   of   a 


V/EWS  OF  G ALTON  AND    WEISMANN  ON  INHERITANCE     1 49 

genetic  line  in  remote  generations  is  also  rare  and  exceptional  ; 
for  the  posterity  of  most  of  the  living  beings  that  now  exist  is 
destined  to  speedy  extinction. 

While  we  may  discover  nothing  in  the  modern  world  to  draw 
together  those  individuals  which,  if  they  were  so  drawn  together, 
might  become  the  parents  of  the  fittest,  this  is  no  evidence  that 
the  fittest  may  not  be,  in  the  long  run,  the  descendants  of  ances- 
tors who  did  bring  together  characteristics  which,  when  thus 
intensified,  were  so  transmitted  to  posterity  as  to  give  to  this 
posterity  an  advantage  over  their  competitors  in  the  struggle  for 
•existence. 


LECTURE   VII 

GALTON   AND   THE   STATISTICAL   STUDY   OF 

INHERITANCE 


LECTURE   VIP— Part  I 

GALTON  AND  THE  STATISTICAL   STUDY   OF  INHERITANCE 

To  talk  about  inheritance  is  much  easier  than  to  study  it.  Of 
the  books  and  essays  which  meet  us  at  every  turn  few  have  much 
basis  in  research,  but  among  the  few  are  those  of  Francis  Galton. 
His  works,  which  have  appeared  at  intervals  during  the  past  twenty 
years,  are  not  speculations,  but  studies.  They  describe  long  and 
thorough  investigations,  carried  out  by  rigorous  methods,  in  lines 
laid  down  on  a  plan  which  has  been  matured  with  great  care  and 
forethought. 

The  simplicity  of  their  language  is  as  notable  as  their  substance. 
Dealing  with  conceptions  which  are  both  new  and  abstruse,  their 
author  finds  our  mother  tongue  rich  enough  for  all  his  needs, 
and  while  the  reasoning  often  taxes  all  our  powers,  there  is  never 
any  doubt  as  to  the  meaning  of  the  words. 

When,  in  rare  cases,  a  technical  term  is  inevitable,  some  famil- 
iar word  is  chosen  with  so  much  aptness  that  it  does  its  duty,  and 
presents  the  new  conception  better  than  any  which  half  a  dozen 
dead  languages  could  afford.  The  terms,  "  mid-parent "  or  "mid," 
"fraternity,"  "nurture,"  and  "Q"  cannot  mislead  or  convey  any 
idea  except  the  right  one. 

My  own  debt  to  Galton  is  great,  and  it  is  acknowledged  with 
gratitude.  Such  acquaintance  with  the  statistical  method  as  I 
possess,  I  owe  to  the  study  of  these  books,  especially  the  ones 
on  "Hereditary  Genius"  (1869),  on  "  Natural  Inheritance"  (1889), 
and  on  "  Finger  Prints  "  (1892). 

My  attempt  to  question  Galton's  generalizations  may  therefore 
seem  ungracious  and  presumptuous,  but   the   uncertainties  of  vital 

1  A  review  of  the  works  of  Francis  Galton;  reprinted  from  the  Popular  Science  Monthly 
for  February  and  March,  1896. 

153 


154  THE  FOUNDATIONS   OF  ZOOLOGY 

Statistics  are  proverbial ;  and  it  is  not  impossible  that  Galton's 
data  may  fail  to  cover  all  the  ground  which  they  should  in  order 
to  prove  his  general  conclusions. 

One  of  these  generalizations  is  so  far-reaching  that  it  must,  if 
well  founded,  lead  to  fundamental  change  in  our  view  of  the 
origin  of  species. 

According  to  Darwin  and  Wallace,  specific  identity  in  living 
things  is  the  outcome  of  the  extermination,  in  the  struggle  for 
existence,  of  the  individuals  which  depart  too  widely  from  that 
"  type  "  which  is,  on  the  whole,  the  best  adapted  to  existing  condi- 
tions. As  these  conditions  change,  the  type  is  also  slowly  modi- 
fied through  a  change  in  the  standard  of  extermination.  Accord- 
ing to  this  view,  the  type  is  the  outcome  of  the  statistical  "  law 
of  error  "  or  the  deviation  from  the  mean,  that  holds  good  in  the 
environment;  and  while  the  "events"  are  properties  of  the  organ- 
ism, the  type  is  fixed  by  the  external  world,  and  not  by  any- 
thing in  the  organism  itself. 

Galton  holds  that  specific  identity  is  not  due  to  the  process  of 
extermination,  but  to  "organic  stability."  As  I  understand  him, 
he  holds  that  this  fills  up  the  gaps  made  by  extermination,  and 
thus  keeps  the  type  intact.  This  "  principle  of  stability,"  which 
is  held  to  result  in  the  persistency  of  types,  is  said  to  be  quite 
independent  of  selection.  "  Genera  and  species  may  be  formed 
without  the  slightest  aid  from  either  natural  or  sexual  selection." 
"  Organic  stability  is  the  primary  factor  by  which  the  distinctions 
between  genera  are  maintained."  Galton  holds,  furthermore,  not 
only  that  specific  stability  is  independent  of  selection,  but  that 
selection  is  "  scarcely  competent "  to  effect  a  change  of  type  "  by 
favoring  mere  varieties  "  —  that  is,  the  ordinary  slight  differences 
between  individuals ;  and  that  it  is  only  when  a  "  sport "  has 
made  its  appearance,  only  when  the  type  has  actually  changed, 
that  selection  can  exert  any  influence.  According  to  this  view 
the  agencies  which  cause  sports  are  the  real  causes  of  the 
mutation  of  species,  and  natural  selection  can  do  no  more  than  to 
exterminate  disadvantageous  sports,  and  thus  favor  advantageous 
ones.  The  "organic  stability"  to  which  so  much  is  attributed  is 
held  to  be  due  to  the  fact  that  the  child  inherits  in  part  from  its 
parents,  and  in  part  from    more    remote   ancestors ;    and    since  the 


G ALTON  AND  STATISTICAL  STUDY  OF  INHERITANCE     1 55 

sum  of  its  ancestry,  or  its  "mid-parentage,"  is,  on  the  average, 
nearer  than  any  exceptional  parent  to  the  mean  of  the  race,  the 
children  of  selected  parents  are,  on  the  average,  more  mediocre 
than  their  parents. 

It  is  quite  possible  that  Galton's  data  may  be  valuable,  and 
that  they  may  be  trustworthy  in  the  study  of  human  faculties,  and 
yet  that  they  may  fail  to  prove  this  generalization ;  and  I  shall 
try  to  show  that  this  is  the  case,  although  I  am  not  sure  I  fully 
grasp  his  point  of  view.  I  assume  that  he  regards  a  zoological 
type,  or  species,  as  something  which  owes  its  origin  to  a  "  principle 
of  stability  "  which  is  not  itself  due  to  selection.  This  is  assuredly 
the  current  interpretation  of  his  statements,  and  it  is  from  this 
standpoint  that  I  shall  examine  his  writings.  If  this  is  not  his 
opinion ;  if  he  in  fact  believes  that  this  "  principle "  owes  its 
existence  to  past  selection ;  if  from  his  data  he  deduces  only  the 
generalization  that  the  results  of  past  selection  may  persist  after 
it  has  ceased  to  act,  —  I  see  no  ground  for  criticism,  for  his  data 
assuredly  prove  this  much,  although  I  cannot  reconcile  his  state- 
ment that  "the  principle  of  stability  is  independent  of  selection" 
with  belief  that  it  is  the  result  of  past  selection. 

Before  we  discuss  the  subject  it  may  be  well  to  ask  what  evi- 
dence there  is  that  the  child  does  inherit  from  any  ancestor  except 
its  parents,  for  descent  from  a  long  line  of  ancestors  is  not  neces- 
sarily equivalent  to  inheritance  from  them,  and  it  is  quite  possible 
that  the  conception  of  a  "  mid-parent "  may  be  nothing  but  a 
logical  abstraction,  useful,  perhaps,  for  statistical  purposes,  but 
without  any  real  existence  in  nature. 

Most  of  its  support  is  derived  from  the  phenomena  of  rever- 
sion or  atavism ;  from  the  appearance,  in  children,  of  ancestral 
features  which  were  not  exhibited  by  the  parents.  While  these 
phenomena  are  real  and  familiar,  we  may  well  doubt  whether 
any  of  them  are  reversions  in  Galton's  sense.  In  some  cases 
we  can  show  that  a  so-called  reversion  is  simply  the  manifesta- 
tion of  a  possibility  which  is  latent  in  the  structure  of  all  the 
normal  members  of  the  species.  The  occurrence,  in  man,  of  a 
distinct  premaxillary  bone  is  an  example  of  this  sort  of  rever- 
sion. It  is  due  to  arrest  of  normal  development,  and  this  arrest 
might    have    happened    to    any    member    of    the    species,    with   the 


156  THE  FOUNDATIONS  OF  ZOOLOGY 

same  result.  We  do  not  know  what  arrested  development,  but 
the  view  that  this  was  some  adverse  circumstance  in  the  history 
of  the  individual  is  surely  more  simple  than  the  opinion  that  the 
child  inherits  its  distinct  premaxilla  from  any  ancestor  except  its 
parent.  The  same  thing  is  true  of  the  polydactylism  of  horses, 
although  this  is  sometimes  attributed  to  reversion  to  miocene 
ancestors. 

When  the  son  of  a  beardless  boy  and  a  beardless  woman 
grows  up  and  acquires  a  beard,  we  may  be  permitted  to  say  he 
has  inherited  his  grandfather's  beard  ;  but  this  is  only  a  figure 
of  speech,  for  he  actually  acquires  nothing  except  what  was  latent 
in  his  parents ;  nor  would  the  case  of  a  bearded  man  descended 
from  a  series  of  ten  or  a  hundred  beardless  boys  and  beardless 
women  be  any  different.  If  we  were  to  propagate  a  plant  by 
cuttings  for  ten  or  a  hundred  generations  under  conditions  which 
did  not  permit  it  to  flower,  and  if,  finally,  we  put  the  last  where 
it  does  flower,  we  should  not  be  justified  in  saying  that  it  does 
not  inherit  its  flower  from  the  preceding  cutting ;  nor  would  the 
case  be  any  different  if,  for  some  reason,  this  preceding  cutting 
could  not  be  made  to  bloom. 

The  phenomena  of  polymorphism  in  insects  and  hydroids 
present  illustrations  of  the  normal  inheritance  of  latent  characters, 
but  we  find  in  them  no  ground  for  the  assertion  that  the  ances- 
tral characters  of  the  medusa  are  not  inherited  from  the  hydroid 
which  produces  it. 

The  sum  of  the  visible  features  of  the  parent,  plus  the  sum 
of  its  latent  potencies,  may  be  called  a  "  mid-parent "  for  statis- 
tical purposes,  if  we  see  fit,  but  there  is  no  evidence  that  this 
"  mid-parent "  is  anything  else  than  the  actual  parent. 

With  this  introductory  note,  we  may  now  enter  upon  the 
study  of  Galton's  works,  the  central  point  of  which  is  as  follows : 
If  we  select  any  one  characteristic  of  a  group  of  animals,  — 
such  a  characteristic  as  the  weight  of  the  individuals,  or  the 
ratio  between  the  length  of  their  arms  and  legs,  or  anything 
else  which  admits  of  exact  numerical  statement,  —  it  will  be 
found  that,  while  no  two  members  of  the  group  are  exactly 
alike,  they  nevertheless  conform  to  a  type,  and  show  the  exis- 
tence of  a  standard,  the  mean  or  average,  to  which  the  majority 


G ALTON-  AND  STATISTICAL   STUDY  OF  INHERITANCE      I  $7 


adhere  pretty  closely,  while  other  members  of  the  group  may 
be  more  abnormal,  showing  marked  deviation  from  the  mean. 
The  deviation  of  these  abnormal  individuals  from  the  mean  is 
not  accidental  or  due  to  "chance,"  for  it  is  part  of  the  orderly 
system  of  nature.  If  the  cases  tabulated  are  numerous  enough, 
the  individuals  will  conform,  so  far  as  this  quality  is  concerned, 
to  what  is  known  in  statistical  science  as  the  law  of  frequency 
of  error.  This  agreement  will  be  so  close,  when  great  numbers  of 
individuals  are  compared,  that  the  number  which  depart  from  the 
mean  to  any  specified  degree  may  be  computed  mathematically. 

For   example,   the   chest   measurements   of    5738   soldiers   gave 
the  following  results  :  — 

If  the  number  of  events  had  been  five 
hundred  thousand  or  five  million  instead  of 
five  thousand,  the  agreement  between  the 
computed  and  observed  frequency  of  each 
degree  of  departure  from  the  mean  would 
have  been  very  much  closer.  When  the 
number  of  cases  is  unlimited,  the  agree- 
ment is  perfect. 

Galton  gives  the  following  illustration 
of  the  significance  of  a  type :  Suppose 
a  large  island  inhabited  by  a  single  race, 
who  intermarry  freely  and  have  lived  for 
many  generations  under  constant  condi- 
tions, then  the  average  heigJit  of  the  adult 
male  of  that   population  will   undoubtedly 

be  the  same  year  after  year.  Also  —  still  arguing  from  the  expe- 
rience of  modern  statistics,  which  are  found  to  give  constant  results 
in  far  less  carefully  guarded  examples  —  we  should  undoubtedly 
find  year  after  year  the  same  proportion  maintained  between  the 
number  of  men  of  different  heights.  I  mean  if  the  average  stature 
were  found  to  be  sixty-six  inches,  and  if  it  were  also  found  in  any 
one  year  that  one  hundred  per  million  exceeded  seventy-eight 
inches,  the  same  proportion  of  one  hundred  per  million  would  be 
closely  maintained  in  all  other  years. 

An     equal     constancy    of     proportion     would     be     maintained 
between    any   other    limits    of    height    we    please    to    specify,    as 


Inches 

Measured 

Computed 

ZZ 

5 

7 

34 

31 

29 

35 

141 

IIO 

36 

322 

323 

37 

732 

732 

38 

1305 

nil 

39 

1867 

1838 

40 

1882 

1987 

41 

1628 

1675 

42 

1148 

1096 

43 

645 

560 

44 

160 

221 

45 

87 

69 

46 

38 

16 

47 

7 

3 

48 

2 

I 

158  THE  FOUNDATIONS  OF  ZOOLOGY 

between  seventy-one  and  seventy-two  inches,  between  seventy-two 
and  seventy-three,  and  so  on.  Now,  at  this  point,  the  law  of 
deviation  from  an  average  steps  in.  It  shows  that  the  number 
per  million,  whose  heights  range  between  seventy-one  and  seventy- 
two  inches,  or  between  any  other  limits  we  please  to  name,  could 
be  predicted  from  the  previous  datum  of  the  average,  and  of  any 
other  one  fact,  such  as  that  of  one  hundred  per  million  exceeding 
seventy-eight  inches. 

Suppose  a  million  of  the  men  to  stand  in  turn  with  their 
backs  against  a  vertical  board  of  sufficient  height,  and  their 
heights  to  be  dotted  off  upon  it.  The  line  of  average  height  is 
that  which  divides  the  dots  into  two  equal  parts,  and  stands,  in 
the  case  we  have  assumed,  at  the  height  of  sixty-six  inches.  The 
dots  will  be  found  to  be  ranged  so  symmetrically  on  either  side 
of  the  line  of  average  that  the  lower  half  of  the  board  will  be 
almost  a  precise  reflection  of  the  upper.  Next,  let  a  hundred 
dots  be  counted  from  above  downwards,  and  let  a  line  be  drawn 
below  them.  According  to  the  conditions,  this  line  will  stand  at 
the  height  of  seventy-eight  inches.  Using  the  data  afforded  by 
these  two  lines,  it  is  possible  to  reproduce  with  extraordinary 
closeness  the  entire  system  of  dots  on  the  board. 

This  law  of  deviation  from  an  average  is  not  restricted  to 
vital  phenomena,  but  holds  true  of  all  events  which  are  the 
resultants  of  variable  conditions,  which  remain  the  same  through 
all  the  events  recorded.  If  the  marks  on  the  board  had  been  made 
by  bullets  fired  at  a  horizontal  line  stretched  in  front  of  a  target, 
they  would  have  been  distributed  according  to  the  same  law,  their 
average  value  would  be  constant,  and  the  deviations  of  the  several 
events  from  the  average  would  be  governed  by  the  same  law,  which 
is  identical  with  that  which  governs  runs  of  luck  at  a  gaming  table. 

Galton  has  described  an  apparatus  which  mimics  in  a  very 
pretty  way  the  conditions  on  which  deviations  from  a  mean 
depend.  It  is  a  long,  shallow  box  set  on  end  and  glazed  in 
front,  leaving  a  depth  of  about  a  quarter  of  an  inch  behind  the 
glass.  Strips  are  placed  in  the  upper  part  to  act  as  a  funnel. 
Below  the  outlet  of  the  funnel  stands  a  succession  of  rows  of  pins 
stuck  fairly  into  the  backboard,  and  below  these,  again,  are  a 
series    of    vertical    compartments.      A    charge    of    small    shot    is 


G ALTON  AND  STATISTICAL  STUDY  OF  INHERITANCE      1 59 

enclosed.  When  the  frame  is  held  topsy-turvy,  all  the  shot  runs 
to  the  upper  end ;  then  when  it  is  turned  back  into  its  working 
position,  the  desired  action  commences. 

The  shot  passes  through  the  funnel  and,  issuing  from  its 
narrow  end,  scampers  deviously  down  through  the  pins  in  a 
curious  and  interesting  way ;  each  one  of  them  darting  a  step  to 
the  right  or  left,  as  the  case  may  be,  every  time  it  strikes  a  pin. 
The  pins  are  so  placed  that  every  shot  strikes  a  pin  in  each 
successive  row.  The  cascade  issuing  from  the  funnel  broadens 
as  it  descends,  and  at  length  every  shot  finds  itself  caught  in  a 
compartment  immediately  after  freeing  itself  from  the  last  row  of 
pins.  The  outline  of  the  columns  of  shot  that  accumulate  in  the 
successive  compartments  approximates  to  the  mathematical  law  of 
frequency,  and  is  closely  of  the  same  shape,  however  often  the 
experiment  is  repeated. 

The  outlines  of  the  columns  would  become  more  nearly  iden- 
tical with  the  normal  law  of  frequency  if  the  rows  of  pins  were 
much  more  numerous,  the  shot  smaller,  and  the  compartments 
narrower ;    also,  if  a  larger  quantity  of  shot  were  used. 

The  principle  on  which  the  action  of  the  apparatus  depends 
is  that  a  number  of  small  accidents  befalls  each  shot  in  its  career. 
In  rare  cases  a  long  run  of  luck  continues  to  favor  the  course 
of  a  particular  shot  towards  either  outside  place,  but  in  the  large 
majority  of  instances  the  number  of  accidents  that  cause  deviation 
to  the  right  balances  in  a  greater  or  less  degree  those  that  cause 
deviation  to  the  left.  Therefore  most  of  the  shot  finds  its  way 
into  the  compartments  that  are  situated  near  to  a  perpendicular 
line  drawn  from  the  outlet  of  the  funnel,  and  the  frequency  with 
which  shots  stray  to  different  distances  diminishes  in  a  much 
faster  ratio  than  these  distances  increase. 

Types  which  are  based  upon  vital  statistics  have  peculiar  interest, 
since  they  persist  from  generation  to  generation,  according  to  the 
law  of  specific  stability,  while  they  also  undergo  slow  changes 
according  to  the  law  of  the  mutability  of  species. 

Individuals  come  and  go,  but  the  type  persists,  and  its  slow 
changes  may  be  pictured  as  quite  independent  of  and  more  substan- 
tial than  the  procession  of  individuals  which  files  past  only  to  vanish 
from  the  world. 


l6o  THE  FOUiVDATIONS   OF  ZOOLOGY 

For  more  than  fifteen  hundred  years  men  of  the  most  acute  and 
well  trained  intellect  devoted  their  lives  to  efforts  to  find  out  in  what 
sense  a  type  exists,  as  contrasted  with  the  individuals  which  exhibit 
it;  yet  the  modern  zoologist  still  finds  himself  face  to  face  with  this 
old  problem,  which,  when  analyzed,  proves  to  be  the  same  as  the 
question :  What  is  the  cause  of  nature  ? 

The  great  intellectual  difference  between  the  schoolmen  of  the 
Middle  Ages  and  the  man  of  science  seems  to  me  to  be  this :  that 
the  modern  student  has  at  last  come  to  see  clearly  that  we  find  in 
nature  no  ultimate  explanation  of  types ;  and  no  reason  to  believe 
that  there  is  anything  in  nature  which  does  not  conform  to  statistical 
laws  and  exhibit  types. 

Statistical  science,  like  all  other  branches  of  science,  helps  us  to 
regulate  our  actions  and  to  act  with  wisdom  and  prudence,  by  mak- 
ing known  to  us  that  order  of  events  which  makes  up  the  system  of 
nature ;  but  discovery  that  events  do  take  place  in  order  is  no  reason 
why  they  should,  or  even  why  they  should  take  place  at  all.  The 
problem  of  the  zoologist  is  not  the  existence  of  types,  but  the  fitness 
of  living  types  for  the  world  around  them,  and  to  my  mind  the 
problem  of  the  "  origin  of  species,"  as  the  zoologist  understands 
these  words,  would  be  greatly  simplified  if  we  clearly  recognize  the 
fact  that  science  holds  out  no  well-grounded  hope  for  any  final 
explanation  of  "  species,"  in  the  logical  sense  of  the  word ;  for  while 
we  may  prove  that  the  occurrence  of  types  is  no  more  nor  less  than 
might  have  been  expected,  this  cannot  show  us  why  the  thing  we 
expect  should  be  the  thing  which  comes  about. 

The  statistical  study  of  vital  types  affords  a  means  for  studying 
the  phenomena  of  inheritance  by  the  exact  methods  of  mathematics, 
and  it  is  capable  of  yielding  definite  and  valuable  results,  so  far  as 
the  vital  phenomena  which  are  studied  can  be  treated  as  if  they 
stood  alone  ;  but  the  attempt  to  generalize  from  vital  statistics,  and 
to  deduce  general  laws  of  inheritance  from  them,  is  attended  by 
peculiar  difificulties,  due  in  great  part  to  the  fact  that  the  data  which 
are  studied  are  not  separable  from  the  organism  which  exhibits  them. 
Stature,  or  size,  or  weight,  may  be  treated  abstractly  for  statistical 
purposes,  but  the  stature  of  an  organism  is  not  an  abstraction,  for 
the  organism  is  not  only  a  bundle  of  properties,  but  a  unit  as  well, 
and  its  stature  is  only  one  of  many  features  which  are  all  beauti- 


G ALTON  AND  STATISTICAL   STUDY  OF  INHERITANCE      l6l 

fully  coordinated  with  each  other  in  such  a  way  as  to  promote  the 
welfare  of  the  species,  A  generalization  which  ignores  this  fact  may, 
while  proved  by  statistics,  be  untrustworthy  as  a  contribution  to  our 
knowledge  of  inheritance. 

In  popular  language,  specific  stability  may  be  said  to  be  due  to 
inheritance,  and  specific  mutability  to  variation ;  but  in  this  connec- 
tion these  words  have  only  a  loose  meaning.  In  so  far  as  they  con- 
vey the  impression  that  the  stability  of  species  and  mutability  of 
species  are  antagonistic  to  each  other,  or  are  due  to  two  distinct  and 
opposing  influences,  these  terms  are  unfortunate,  for  we  have  good 
ground  for  believing  that  they  are  only  contrasted  aspects  of  the  same 
phenomenon  —  the  extermination  of  certain  individual  peculiarities, 
and  the  preservation  of  others,  by  natural  selection. 

The  older  naturalists  held  that  adherence  to  type  is  due  to  some 
innate  principle  of  specific  stability  which  is  an  essential  and  immu- 
table attribute  of  each  species  of  living  things  ;  but  the  accumulation 
of  conclusive  evidence  of  the  mutability  of  species  has  driven  this 
conception  out  of  the  field.  Most  naturalists  now  regard  the  type  as 
nothing  but  that  normal  which  is  most  perfectly  fitted  to  the  environ- 
ment, and  they  hold  that  it  is  kept  true  through  the  extinction  of 
aberrant  individuals  by  selection. 

According  to  this  view,  which  seems  to  be  supported  by  ample 
evidence,  the  stability  of  species  is  due  to  survival — to  the  same 
mechanism  which  brings  about  the  mutability  of  species.  They  hold 
that  neither  the  stability  nor  the  mutability  of  species  is  anything 
more  than  the  struggle  for  existence  would  lead  one  to  expect ;  and 
that  which  we  call  inheritance  and  that  which  we  call  variation  not 
two  things,  but  one  thing  in  two  points  of  view. 

Galton  is  led  by  his  statistical  studies  of  vital  characters  to  a 
view  which  bears  an  odd  resemblance  to  that  of  the  older  naturalists ; 
for,  according  to  him,  the  principle  which  results  in  the  permanency 
of  types  is  quite  independent  of  selection. 

He  shows,  for  example,  by  the  statistical  study  of  stature,  that 
the  type  of  human  stature  is  very  constant  from  generation  to  gener- 
ation, although  the  statistics  of  marriage  show  that  there  is  no  con- 
trolling tendency  for  persons  of  like  stature  to  marry.  He  also 
shows  that  the  children  of  parents  who  are  both  tall  or  both  short  do 
not  on  the  average  have  the  stature  of  their  parents,  but  are  nearer 

M 


1 62  THE  FOUNDATIONS   OF  ZOOLOGY 

than  they  to  the  mean  for  the  race.  These  facts,  and  others  like 
them,  are  held  to  prove  the  existence  of  a  principle  of  stability 
independent  of  selection. 

In  his  more  recent  work  on  the  patterns  of  human  fingers  he 
says  that,  since  it  has  been  shown  (Chapter  XII.)  that  the  character 
of  the  finger  prints  is  practically  identical  in  Englishmen,  Welsh- 
men, Jews,  negroes,  and  Basques,  the  same  familiar  patterns  appear- 
ing in  all  of  them  with  much  the  same  degree  of  frequency,  and  that 
persons  belonging  to  different  classes,  such  as  students  in  science 
and  students  in  art,  farm  laborers,  men  of  culture,  and  the  lowest 
idiots  in  the  London  district,  show  no  decided  difference  in  their 
finger  prints,  it  seems  to  be  proved  that  no  sensible  amount  of  cor- 
relation exists  between  any  of  the  patterns  on  the  one  hand  and  any  of 
the  bodily  faculties  and  characteristics  on  the  other.  It  seems  absurd, 
therefore,  to  hold  that,  in  the  struggle  for  existence,  a  person  with, 
say,  a  loop  on  his  right  middle  finger  has  a  better  chance  of  survival 
or  a  better  chance  of  early  marriage  than  one  with  an  arch.  Conse- 
quently, genera  and  species  are  here  seen  to  be  formed  without  the 
slightest  aid  from  either  natural  or  sexual  selection,  and  these  finger 
patterns  are  apparently  the  only  peculiarity  in  which  panmyxia,  or 
the  effect  of  promiscuous  marriage,  admits  of  being  studied  on  a 
large  scale. 

He  says  that  the  results  of  panmyxia  in  finger-markings  cor- 
roborate his  arguments  in  "Natural  Inheritance"  and  elsewhere 
to  show  that  "organic  stability"  is  the  primary  factor  by  which 
the  distinctions  between  genera  are  maintained.  Consequently, 
the  progress  of  evolution  is  not  a  smooth  and  uniform  progres- 
sion, but  one  that  proceeds  by  jerks,  through  successive  "sports," 
as  they  are  called,  some  of  them  implying  considerable  organic 
changes,  and  each  in  turn  being  favored  by  natural  selection. 

Galton's  explanation  of  this  specific  stability  is  as  follows :  The 
child  inherits  in  part  from  the  parents,  in  part  from  more  remote 
ancestors ;  and  since  the  sum  of  its  ancestry,  or,  as  Galton  calls 
it,  the  "mid-parentage,"  is  on  the  average  nearer  than  the  excep- 
tional parents  to  the  mean  for  the  race,  the  children  of  selected 
parents  are  on  the  average  more  mediocre  than  their  parents. 

I  have  tried  to  show  that,  while  the  child  is  descended  from  a 
long  line  of  ancestors,  it  inherits  from  none  but  the   parents,  and 


GALTON  AND   STATISTICAL  STUDY  OF  INHERITANCE    163 

that  it  can  only  be  said  in  a  figurative  sense  to  iniierit  from  more 
remote  ancestors.  I  shall  soon  refer  to  proof  that  the  persistency 
of  adaptive  types  is  due  to  natural  selection,  and  not  to  any  prin- 
ciple of  organic  stability  which  is  independent  of  selection,  although 
this  view  itself  at  once  brings  up  difficulties. 

If  it  be  true,  if  the  stability  of  adaptive  types  is  due  to  the 
survival  of  the  fittest,  why  do  we  have  a  type  and  not  a  fixed 
standard .-'  If  speed  and  courage  and  strength  are  good  things, 
why  is  not  every  surviving  individual  as  swift  as  the  swiftest,  as 
brave  as  the  bravest,  and  as  strong  as  the  strongest .''  Why  does 
not  every  individual  have  every  useful  quality  developed  to  the 
highest  excellence  which  it  may  reach  in  any  individual  of  the 
species }  Why  should  we  find  that  diversity  among  individuals 
which  usually  passes  under  the  name  of  "variation".'' 

We  can  measure  strength  and  can  treat  it  abstractly,  and  we  can 
artificially  select  and  breed  from  the  strongest  members  of  a  stock, 
neglecting  all  other  features ;  but  this  is  not  what  happens  in 
nature.  Here  the  most  favored  individuals  are  not  the  strongest, 
but  the  ones  in  which  all  the  qualities  of  the  species  are  most 
perfectly  coordinated  with  each  other  in  relation  to  the  external 
world.  Excessive  strength  may  involve  deficiency  in  some  other 
essential,  and  the  mean  or  average  strength  of  the  species  is  that 
degree  of  strength  which  is  most  in  harmony  with  the  mean  degree 
of  development  of  all  the  other  characteristics  of  the  species,  and 
the  individuals  which  depart  too  widely  from  this  mean,  either 
through  excess  or  deficiency  of  strength,  are  the  ones  which  are 
ultimately  exterminated. 

Galton  has  himself  given  such  a  clear  statement  of  the  way  a 
type  is  established  by  selection  that  it  cannot  be  improved  upon, 
and  I  quote  it  in  his  own  words:  "Suppose,"  he  says,  "that  we 
are  considering  the  stature  of  some  animal  that  is  liable  to  be 
hunted  by  certain  beasts  of  prey  in  a  particular  country.  So  far 
as  he  is  big  of  his  kind,  he  would  be  better  able  than  the  medi- 
ocres  to  crush  through  the  thick  grass  and  foliage  whenever  he 
was  scampering  for  his  life,  to  jump  over  obstacles,  and  possibly 
to  run  somewhat  faster  than  they.  So  far  as  he  is  small  of  his 
kind,  he  would  be  better  able  to  run  through  narrow  openings, 
to    make    quick   turns,  and    to    hide    himself.       Under   the   general 


164  THE  FOUNDATIONS  OF  ZOOLOGY 

circumstances  it  would  be  found  that  animals  of  some  particular 
stature  had  on  the  whole  a  better  chance  of  escape  than  any- 
other  ;  and  if  their  race  is  closely  adapted  to  these  circumstances 
in  respect  to  stature,  the  most  favored  stature  would  be  identical 
with  the  mean  of  the  race.  Though  the  impediments  to  flight  are 
less  unfavorable  to  this  (stature)  than  to  any  other,  they  will  differ  in 
different  experiences.  The  course  of  an  animal  might  chance  tO' 
pass  through  denser  foliage  than  usual,  or  the  obstacles  in  his 
way  may  be  higher.  In  that  case  the  animal  whose  stature 
exceeded  the  mean  would  have  an  advantage  over  mediocrities. 
Conversely,  the  circumstances  might  be  more  favorable  to  a  small 
animal.  Each  particular  line  of  escape  might  be  most  favorable 
to  some  particular  stature,  and,  whatever  this  might  be,  it  might 
in  some  cases  be  more  favored  than  any  other.  But  the  acci- 
dents of  foliage  and  soil  in  a  country  are  characteristic  and  per- 
sistent, and  may  fairly  be  considered  as  approximating  to  a  typical 
kind.  Therefore  those  which  most  favor  the  animals  of  the  mean 
stature  will  be  more  frequently  met  with  than  those  which  favor 
any  other  stature,  and  the  frequency  of  the  latter  occurrence  will 
diminish  rapidly  as  the  stature  departs  from  the  mean. 

"  It  might  well  be  that  natural  selection  would  favor  the 
indefinite  increase  of  numerous  separate  faculties  if  their  improve- 
ment could  be  effected  without  detriment  to  the  rest ;  then  medi- 
ocrity in  that  faculty  would  not  be  the  safest  condition.  Thus  an 
increase  of  fleetness  would  be  a  clear  gain  to  an  animal  liable  to- 
be  hunted  by  beasts  of  prey,  if  no  other  useful  faculty  were 
thereby  diminished. 

"But  a  too  free  use  of  this  'if'  would  show  a  jaunty  disre- 
gard of  a  real  difficulty.  Organisms  are  so  knit  together  that 
change  in  one  direction  involves  change  in  many  others ;  these 
may  not  attract  attention,  but  they  are  none  the  less  existent. 
Organisms  are  like  ships  of  war,  constructed  for  a  particular  pur- 
pose in  warfare,  as  cruisers,  line-of-battle  ships,  etc.,  on  the  prin- 
ciple of  obtaining  the  utmost  efficiency  for  their  special  purpose. 
The  result  is  a  compromise  between  a  variety  of  conflicting  de- 
siderata, such  as  cost,  speed,  accommodation,  stability,  weight  of 
guns,  thickness  of  armor,  quick  steering  power,  and  so  on.  It  is 
hardly  possible    in   a    ship    of    any  established    type    to    make    an 


GALTON  AND  STATISTICAL  STUDY  OF  INHERITANCE     165 

improvement  in  any  one  of  these  respects  without  a  sacrifice  in 
other  directions.  If  the  fleetness  is  increased,  the  engines  must 
be  larger,  and  more  space  must  be  given  up  to  coal,  and  this 
diminishes  the  remaining  accommodation. 

"  Evolution  may  produce  an  altogether  new  type  of  vessel  that 
shall  be  more  efficient  than  the  old  one,  but  when  a  particular 
type  has  become  adapted  to  its  functions,  through  long  experience, 
it  is  not  possible  to  produce  a  mere  variety  of  its  type  that  shall 
have  increased  efficiency  in  some  one  particular  without  detriment 
to  the  rest.     So  it  is  with  animals." 

Neo-Lamarckians  are  fond  of  asserting  that  natural  selection 
cannot  bring  about  an  adaptation  which  involves  the  coordinated 
modification  of  many  correlated  parts;  and  they  may  be  inter- 
ested in  the  clear  demonstration  which  I  have  quoted  from 
Galton  of  the  way   natural  selection  brings  about  coordination. 

His  assertion  that  after  a  coordinated  type  has  been  estab- 
lished it  cannot  be  changed  by  the  mere  selection  of  individual 
differences,  seems  to  be  well  founded,  so  far  as  the  modification 
by  artificial  selection  of  a  type  which  has  been  established  by 
natural  selection  is  in  question.  As  it  is  with  vessels,  so  it  is 
with  animals  in  the  hands  of  a  breeder  who,  having  in  mind 
some  one  point  of  excellence,  picks  out  the  individual  animals  in 
which  the  desired  peculiarity  is  most  marked,  and,  propagating 
from  them,  destroys  all  the  others. 

A  breeder  of  domesticated  animals  or  of  cultivated  plants, 
who  devotes  his  attention  to  one  or  two  characteristics,  must  soon 
reach  a  point  where  no  further  improvement  is  practicable  unless 
the  species  is  at  the  same  time  greatly  modified  in  many  other 
respects.  This  fact  does  not  prove  that  specific  stability  is  due 
to  anything  else  than  selection,  but  only  that  no  great  change 
is  possible  without  the  coordinated  modification  of  all  the  corre- 
lated features,  and  this  is  just  what  we  should  expect,  on  Galton's 
own  showing,  as  the  effect  of  long  ages  of  selection.  Here,  as  in 
so  many  other  cases,  artificial  selection  proves  to  be  an  imperfect 
analogy ;  for  while  the  breeder  may  utterly  destroy  all  the  animals 
except  the  few  which  he  positively  selects,  extermination  in  the 
struggle  for  existence  is  often  so  slow  as  to  be  imperceptible. 
Before    a   failing   genetic    line   is    utterly  cut  off,   it   may  continue 


1 66  THE  FOUNDATIONS   OF  ZOOLOGY 

to  lose  ground  for  many  generations,  during  which  there  are 
innumerable  opportunities  for  every  useful  quality  to  count  for 
all  it  is  worth.  The  survivors  are  the  ones  in  which  all  these 
useful  qualities  are  most  perfectly  coordinated,  and  the  effect  of 
the  struggle  is  to  make  this  coordination  more  and  more  perfect, 
although  we  must  remember  that  no  essential  change  can  occur 
in  a  type  unless  some  change  in  the  external  world  makes  a 
place  for  a  new  type. 

"That  natural  selection  generally  acts  with  extreme  slowness," 
says  Darwin,  "  I  fully  admit.  It  can  act  only  when  there  are 
places  in  the  natural  polity  of  a  district  which  can  be  better 
occupied  by  the  modification  of  some  of  its  existing  inhabitants. 
The  occurrence  of  such  places  will  often  depend  on  physical 
changes,  which  generally  take  place  very  slowly,  and  on  the  im- 
migration of  better  adapted  forms  being  prevented.  As  some  few 
of  the  old  inhabitants  become  modified,  the  mutual  relations  of 
others  will  often  be  disturbed ;  and  this  will  create  new  places, 
ready  to  be  filled  up  by  better  adapted  forms ;  but  all  this  will 
take  place  very  slowly.  Although  all  the  individuals  of  the  same 
species  differ  in  some  slight  degree  from  each  other,  it  would  often 
be  long  before  differences  of  the  right  nature  in  various  parts  of 
the  organization  might  occur."  ^ 

The  passage  I  have  quoted  from  Galton  seems  to  indicate  that, 
after  all,  he  may  believe  that  the  specific  types  of  zoology  and 
botany  are  nothing  more  than  the  persistent  effects  of  past  selec- 
tion, and  that  his  statement  that  "organic  stability  is  independent 
of  selection  "  may  refer  to  present  selection  only. 

These  statements  are  clear  and  explicit,  however,  and  they  have 
been  interpreted  by  most  readers  as  a  flat  contradiction  of  the 
view  that  the  mechanism  which  leads  to  the  formation  of  new 
types  is  identical,  on  its  vital  side,  with  that  which  preserves  es- 
tablished types ;  the  view  that  the  differences  between  the  two 
are  differences  in  the  external  world. 

He  S2i.ys  {Nattire,  September,  1885):  "It  is  some  years  since  I 
made  an  extensive  series  of  experiments  in  the  produce  of  seeds 
of  different  sizes,  but  of  the  same  species.  ...  It  appears  from 
these  experiments  that  the  offspring  did  ftot  tend  to  resemble  their 

^  "Origin  of  Species,"  p.  84. 


G  ALTON  AND   STATISTICAL   STUDY  OF  INNER  FT ANCE      1 67 

parent  seeds  in  size,  but  to  be  always  more  mediocre  than  they ; 
to  be  smaller  than  they  if  the  parents  were  large ;  to  be  larger 
than  the  parents  if  the  parents  were  very  small."  He  says  that 
this  regression  is  a  necessary  result  of  the  fact  that  "the  child 
inherits,  partly  from  his  parents,  partly  from  his  ancestors.  Speak- 
ing generally,  the  further  his  genealogy  goes  back,  the  more 
numerous  and  varied  will  his  ancestors  become,  until  they  cease 
to  differ  from  any  equally  numerous  sample  taken  at  hap-hazard 
from  the  race  at  large.  Their  mean  stature  will  then  be  the  same 
as  that  of  the  race ;  in  other  words,  it  will  be  mediocre." 

He  illustrates  this  by  comparing  the  results  of  the  combination 
in  the  child  of  the  mean  stature  of  the  race  with  the  peculiarities 
of  its  parents  to  the  result  of  pouring  an  uniform  proportion  of 
pure  water  into  a  vessel  of  wine.  It  dilutes  the  wine  to  a  certain 
fraction  of  its  original  strength,  whatever  that  strength  may  have 
been. 

He  then  goes  on  to  the  deduction  that  the  law  of  regression 
to  the  type  of  the  race  "tells  heavily  against  the  full  hereditary 
transmission  of  any  rare  and  valuable  gift,  as  only  a  few  of 
many  children  would  resemble  their  parents.  The  more  excep- 
tional the  gift,  the  more  exceptional  will  be  the  good  fortune  of  a 
parent  who  has  a  son  who  equals,  and  still  more  if  he  has  a  son 
who  surpasses  him.  The  law  is  even-handed ;  it  levies  the  same 
heavy  succession  tax  on  the  transmission  of  badness  as  well  as 
goodness.  If  it  discourages  the  extravagant  expectations  of  gifted 
parents  that  their  children  will  inherit  all  their  powers,  it  no 
less  discountenances  the  extravagant  fears  that  they  will  inherit 
all  their  weaknesses  and  diseases.  .  .  .  Let  it  not  for  a  moment 
be  supposed  that  the  figures  invalidate  the  general  doctrine  that 
the  children  of  a  gifted  pair  are  much  more  likely  to  be  gifted 
than  the  children  of  a  mediocre  pair ;  what  it  asserts  is  that  the 
ablest  of  the  children  of  one  gifted  pair  is  not  likely  to  be  as 
gifted  as  the  ablest  of  all  the  children  of  many  mediocre  pairs." 

In  his  recent  work  on  "  Finger  Prints  "  he  says  :  "  It  is  impossi- 
ble not  to  recognize  the  fact  so  clearly  illustrated  by  these  patterns 
in  the  thumbs  that  natural  selection  has  no  monopoly  of  influence 
in  the  construction  of  genera,  but  that  it  could  be  wholly  dis- 
pensed   with,  the    internal    conditions    acting   by   themselves   being 


1 68  THE  FOUNDATIONS  OF  ZOOLOGY 

sufficient.  Not  only  is  it  impossible  to  substantiate  a  claim  for 
natural  selection  that  it  is  the  sole  agent  in  forming  genera,  but 
it  seems,  from  the  experience  of  artificial  selection,  that  it  is 
scarcely  competent  to  do  so  by  favoring  mere  varieties  in  the 
sense  in  which  I  understand  the  term.  Mere  varieties  from  a 
common  typical  centre  blend  freely  in  the  offspring,  and  the  off- 
spring of  every  race  where  statistical  characters  are  constant,  neces- 
sarily tend,  as  I  have  shown,  to  regress  toward  their  common 
typical  centre.  A  mere  variety  can  never  establish  a  sticking 
point  in  the  forward  course  of  evolution." 

Galton  therefore  holds  that,  while  specific  stability  is  due  to 
inheritance  from  a  long  line  of  ancestors,  the  transmutation  of 
species  is  due  to  the  sudden  appearance  of  "sports,"  which,  if  use- 
ful, are  seized  upon  and  perpetuated  by  selection. 

He  says  that  a  sport  is  a  substantial  change  of  type  effected 
by  a  number  of  small  changes  of  typical  centre,  each  more  or  less 
stable,  and  each  being  in  its  turn  favored  and  established  by  natural 
selection  to  the  exclusion  of   its  competitors. 

"  The  distinction  between  a  mere  variety  and  a  sport  is  real 
and  fundamental." 

This  generalization,  based  upon  numerical  data,  is  so  funda- 
mental and  far-reaching  that  a  critical  discussion  of  the  evidence 
is  most  important. 


LECTURE    VII— Part    II 

It  may  be  well  to  remind  those  who  are  not  familiar  with  statis- 
tical reasoning  that  a  type  may  exhibit  the  influence  of  inheritance, 
and  yet  be  of  no  value  as  a  basis  for  generalization  on  inheritance. 

The  bullet  type  shows  the  influence  of  aim,  but  if  we  use  it  to 
test  the  accuracy  of  aim  or  the  excellence  of  the  rifle,  we  may  be  led 
astray  if  some  other  influence,  such  as  the  weight  of  the  bullet,  act 
on  all  or  on  a  majority  of  the  shots,  and  escape  detection.  In  this 
case  the  type  may  seem  to  prove  that  the  rifle  is  inaccurate  or  im- 
properly aimed  when  it  is  not,  and  we  cannot  assume  that  because 
a  type  shows  the  influence  of  aim  it  is  a  test  of  aim. 

So  a  characteristic  or  a  group  of  characteristics  of  living  things 
may  conform  to  the  mathematical  law  of  deviation  from  a  mean, 
and  may  thus  form  a  type,  and  this  type  may  show  the  influence  of 
inheritance,  without  being  a  safe  basis  for  generalization  regarding 
inheritance. 

This  may  be  illustrated  by  an  example.  If  we  were  to  tabulate 
the  prices  of  all  the  horses  sold  within  a  given  period,  we  should 
undoubtedly  find  that  they  would  conform  to  a  type ;  that  there  is 
a  mean  or  average  price  ;  that  the  horses  which  fetch  more  than 
this  price  are  equal  in  number  to  those  which  fetch  less,  and  that 
the  prices  group  themselves  about  the  mean  according  to  the  law  of 
error.  If  the  term  be  long  enough  to  include  several  generations, 
we  shall  find  that  inheritance  or  "blood"  has  a  marked  influence 
on  price,  and  that  the  children  of  high  priced  horses  are  much 
more  likely  than  horses  selected  at  random  to  bring  the  same 
high  prices.  The  type  will  exhibit  the  influence  of  inheritance,  but 
it  will  be  of  no  value  in  studying  inheritance  unless  we  can  in  some 
way  separate  the  influence  of  blood  from  the  influence  of  supply  and 
demand  which  has  far  more  to  do  with  the  average  price  and  with 
the  type. 

169 


I/O  THE  FOUNDATIONS   OF  ZOOLOGY 

That  the  price  of  horses  is,  on  the  whole,  fixed  like  that  of  other 
commodities,  is  obvious,  and  it  is  also  clear  that  the  type  may  be 
changed  by  events  which  have  no  relation  to  inheritance,  such  as 
the  application  of  electricity  to  street  cars, 

A  change  of  this  sort,  such  as  took  place  when  steam  replaced 
stage  coaches,  is  a  "  sport "  or  sudden  and  fundamental  change  of 
type,  but  this  may  also  be  changed  by  slight  and  gradual  modifica- 
tion with  the  slow  growth  of  a  complicated  civilization  and  an 
increased  demand  for  horses. 

As  inheritance  has  an  influence  on  the  price  of  horses,  what  will 
be  the  result  if  we  destroy  the  children  of  all  horses  which  fetch  less 
than  +2  of  Galton's  scheme,  and  breed  from  only  that  fourth  of  the 
whole  which  sell  for  more  than  75  per  cent  of  his  centesimal  scale  ? 

We  may,  at  first,  get  fancy  prices  for  our  expensive  stock,  but 
if  selection  cease  with  this  first  step,  and  we  supply  as  many  colts 
as  before,  the  price  will  "revert"  to  the  type,  and  the  mean  will 
become  the  same  as  it  was. 

Does  this  prove  that  those  qualities  in  horses  for  which  money 
is  paid  have  "  retrograded  to  mediocrity  "  in  these  descendants  of 
high-priced  horses  ?  It  proves  nothing  of  the  sort,  for  the  qualities 
which  command  a  price  are  one  thing,  and  the  price  another.  Even 
if  the  horses  have  much  more  of  these  qualities  than  the  old  stock, 
the  price  will  still  be  fixed  by  the  ratio  between  demand  and 
supply,  and  while  blood  will  tell   in   use,  it  will  not  tell  in   price. 

It  is  clear,  then,  that  characteristics  of  living  things  which  are 
influenced  by  inheritance  may  conform  to  a  type  which  exhibits 
"  specific  stability,"  "  regression  to  mediocrity,"  an  occasional 
"  sport,"  and  all  the  other  properties  of  the  types  which  Galton  has 
studied,  without  furnishing  proof  that  "  inherited  "  qualities  behave 
in  the  same  way.  To  prove  this,  we  must  cancel,  or  neutralize, 
or  make  allowance  for,  all  the  factors  which  have  an  influence  upon 
the  type,  except  "inheritance." 

Galton's  generalizations  upon  the  laws  of  inheritance  from  the 
statistical  study  of  finger  prints  rest  upon  the  belief  that  the 
patterns  are  inherited.  If  they  are  not,  they  can  teach  nothing 
of  inheritance,  when  considered  in  themselves,  without  farther 
analysis.  He  proves  that  they  are,  to  some  degree,  dependent, 
either  directly  or  indirectly,  upon  inheritance,  just  as  the  price  of 


G ALTON  AND  STATISTICAL  STUDY  OF  INHERITANCE     171 

horses  is,  but  this  is  not  enough.  To  warrant  his  deductions,  he 
must  either  prove  that  inheritance  is  the  controlHng  factor  in  fixing 
the  type,  or  else  he  must  show  that,  in  the  long  run,  all  the  other 
factors  will  balance  ;  and  this,  it  seems  to  me,  he  fails  to  prove. 
He  has  studied,  in  150  fraternal  couples,  or  children  of  the  same 
parents,  the  frequency  with  which  the  same  pattern  occurs  on  the 
same  finger  of  both,  and  he  finds  that,  when  marked  on  a  scale  in 
which  o  indicates  no  resemblance,  and  100°  the  greatest  possible 
relationship,  they  show  10°  of  relationship.  This  number  is  great 
enough  to  prove  the  influence  of  inheritance,  but  it  seems  to  me 
to  be  too  small  to  show  that  the  patterns  are  themselves  directly 
inherited;  for  it  seems  to  me  to  indicate  that  they  are  indirectly 
influenced  by  some  other  inherited  character,  such,  perhaps,  as  the 
ratio  between  the  growth  in  the  embryo  of  the  ball  of  the  finger 
and  that  of  the  nail. 

Inheritance  is  not,  unfortunately,  a  word  which  is  always  used 
with  scientific  precision,  for  it  has  many  meanings.  Most  of  the 
qualities  which  give  a  horse  its  value  in  the  market,  as  compared 
with  other  horses,  are  due  to  breeding,  but  this  word  has  many 
meanings.  Orlando  says:  "His  horses  are  ^r^^  better;  for  besides 
that  they  are  fair  with  their  feeding,  they  are  taught  their  man- 
age, and  to  that  end  riders  dearly  hired."  The  "breeding  jennet, 
lusty,  young,  and  proud,"  seems  to  be  a  wild  mare,  with  no 
breeding  in  the  first  sense,  and  the  horse  which  did  not  lack 
what  a  horse  should  have,  "  Round-hoofed,  short-jointed  fetlocks 
shag  and  long,  Broad  breast,  full  eye,  small  head,  and  nostrils 
wide.  High  crest,  short  ears,  straight  legs,  and  passing  strong. 
Thin  mane,  thick  tail,  broad  buttocks,  tender  hide,"  is  a  thoroiigh- 
bi'ed. 

Recent  speculations  have  forced  us  to  attend  to  the  difference 
between  these  meanings  of  the  word.  In  the  last  sense  breeding 
is  the  influence  of  ancestry,  and  it  may  practically  be  treated  as 
synonymous  with  the  word  ancestry.  In  the  first  sense,  breeding, 
broadly  used,  is  that  influence  of  the  ontogenetic  environment  for 
which  that  most  objectionable  term,  "acquired  characters,"  has 
been  thoughtlessly  adopted ;  for  no  one  who  believes  that  species 
are  mutable  can  believe  that  there  is  any  character  which  has  not 
been  "  acquired." 


1/2  THE  FOUNDATIONS  OF  ZOOLOGY 

In  his  earlier  writings  Galton,  borrowing,  I  suppose,  from  "  The 
Tempest,"  uses  the  word  nurture  to  designate  what  is  commonly 
called  acquired  characters,  and  this  term  is  so  apt  and  expressive 
that  it  should  not  be  permitted  to  pass  out  of  use,  for  it  may  be 
given  a  definite  technical  meaning  without  violence  to  its  ordinary 
use.  Using  nurture  instead  of  acquired  characters  for  the  influence 
of  the  environment  of  the  individual,  we  may  speak  of  the  two 
elements  of  breeding  as  ajicestry  and  nurture. 

It  is  obvious  at  the  present  day  that  our  studies  of  inheritance 
can  have  little  value  unless  we  distinguish  between  these  two 
factors ;  for  many  naturalists  hold  that  there  is  good  ground  for 
asking  whether  the  effects  of  nurture  are  ever  inherited,  and  most 
naturalists  admit  that  it  is  possible  that  the  value  of  these  two 
elements  in  breeding  may  be  very  different. 

If  breeding  is  to  be  studied  by  the  statistical  method,  for  the 
purpose  of  exhibiting  the  laws  of  inheritance,  we  must  employ 
types  in  which  we  can  separate  the  effects  of  ancestry  from  the 
effects  of  nurture ;  for  if  we  make  use  of  types  which  do  not  admit 
of  this  analysis,  our  results  may  tell  us  no  more  of  inheritance  than 
the  scheme  of  prices  tells  us  of  the  value  of  blood  in  horses. 

If,  as  many  teach,  inheritance  is  the  equivalent  to  ancestry, 
and  nurture  is  never  inherited,  no  type  in  which  these  two  factors 
are  combined  can  tell  us  anything  about  inheritance. 

It  seems  probable  to  me  that  the  resemblance  which  Galton 
points  out  between  the  finger  marks  of  fraternal  couples  may  be 
due  to  nurture,  in  this  broad  sense  of  the  word,  and  not  to  inheri- 
tance, for  there  is  ample  evidence  that  the  value,  in  breeding,  of 
a  given  parental  characteristic  does  depend  upon  its  origin,  and 
that  one  due  to  nurture  has  a  very  different  value  from  one  which 
is  itself  inherited. 

Of  the  2459  deaf  pupils  of  the  American  Asylum,  nearly  600 
have  married,  and  have  become  the  parents  of  over  800  children, 
of  whom  104,  or  more  than  12  per  cent,  were  born  deaf  —  a 
ratio  which  is  great  enough  to  prove  that  inheritance  has  some 
influence.  Analysis  of  the  record  shows  clearly,  however,  that 
these  deaf  children  are  not  uniformly  distributed  among  the 
married  pupils  of  the  asylum,  but  that  the  result  is  influenced  by 
the    character    of    the    parental   deafness.     From  283    of    the    596 


G ALTON  AND  STATISTICAL   STUDY  OF  INHERITANCE      1 73 

marriages  no  children  are  reported,  while  from  three  other  families 
no  report  is  made  except  that  all  the  children  hear,  so  that  the 
811  children  which  are  reported  are  from  only  304  families,  and 
in  many  of  these  only  one  parent  was  deaf.  Of  the  loi  children 
of  40  of  these  marriages  none  are  reported  as  deaf,  and  all  but 
II  are  reported  as  hearing,  and  the  710  children  are  from  the 
remaining  264  marriages.  In  52  of  the  marriages  both  father  and 
mother  were  congenitally  deaf,  and  these  are  the  parents  of  48 
out  of  the  104  congenitally  deaf  children,  but  they  are  the  parents 
of  only  151  of  the  total  number  of  811  children,  and  nearly  32 
per  cent  of  all  the  children  of  these  congenitally  deaf  parents 
are  congenitally  deaf. 

In  two  of  the  groups  in  which  the  marriages  may  be  classified 
the  number  of  marriages  and  the  number  of  children  are  about 
equal,  but  there  is  a  most  remarkable  difference  in  the  number  of 
deaf  children. 

In  55  marriages,  with  139  children,  both  parents  are  reported 
as  adventitiously  deaf,  while  in  52  marriages,  with  151  children, 
both  were  congenitally  deaf.  In  the  latter  group,  52  children,  or 
31.78  per  cent,  are  congenitally  deaf,  only  88  are  stated  to  hear, 
and  no  facts  are  given  about  the  hearing  of  15  of  them.  In  the 
first  group  only  4  of  the  139  children,  or  "i^.^j  per  cent,  are  re- 
ported as  congenitally  deaf,  129  are  reported  as  hearing,  and  6  are 
not  reported. 

I  have  divided  all  the  marriages  into  four  groups :  In  one 
all  the  children  hear ;  in  the  second  5  to  6  per  cent  are  deaf ; 
in  the  third  from  12  to  18  per  cent  are  deaf;  and  in  the  fourth 
31.78  per  cent  are  deaf.  In  the  first  group,  in  which  all  the 
children  hear,  5  of  the  marriages,  with  18  children,  are  be- 
tween a  hearing  husband  and  a  wife  who  is  adventitiously  deaf; 
I  marriage,  with  4  children,  between  a  hearing  man  and  a  woman 
the  source  of  whose  deafness  is  not  stated;  6  marriages,  with  13 
children,  where  wife  hears  and  husband  is  adventitiously  deaf  ,- 
23  marriages,  with  51  children,  where  husband  is  adventitiously- 
deaf,  and  wife  deaf  from  unknown  causes;  2  marriages,  with  6 
children,  where  both  were  deaf  from  unknown  causes;  i  marriage, 
with  4  children,  where  husband  is  deaf  from  unknown  causes  and 
wife  hears  ;  and  2  marriages,  with    5   children,   where  wife  is  con- 


174  THE  FOUNDATIONS  OF  ZOOLOGY 

genitally  deaf,  and  husband  deaf  from  unknown  causes.  None  of 
the   loi    children   of   these   40    marriages   are  reported    as  deaf. 

In  the  second  group,  where  5  to  6  per  cent  of  the  children 
are  deaf,  87  are  the  children  of  37  marriages  where  the  hus- 
band was  congenitally  deaf  and  wife  adventitiously  deaf ;  and 
139  are  the  children  of  55  marriages  where  both  husband  and 
wife  were  adventitiously  deaf.  We  must  bear  in  mind,  while 
considering  this  last  case,  that  adventitious  deafness  may  indicate 
an  hereditary  predisposition ;  for  many  of  the  pupils  of  the  asylums 
who  lost  their  hearing  after  birth  have  deaf  relatives,  and  thus  show 
that  their  deafness  is  not  strictly  adventitious,  in  the  scientific  sense, 
but  is  due  to  a  congenital  predisposition  to  deafness. 

In  the  third  class,  where  from  12  to  18  of  the  children  are 
congenitally  deaf,  124  are  the  children  of  51  marriages  where 
husband  was  adventitiously  and  wife  congenitally  deaf ;  66  were 
children  of  16  marriages  of  hearing  husband  and  congenitally 
deaf  wife ;  72  were  children  of  26  marriages  where  wife  hears 
and  husband  is  congenitally  deaf;  and  71  of  29  marriages  of  con- 
genitally deaf  husband  with  wife  deaf  from  unknown  causes.  In 
all  the  families  in  this  group  one  parent  was  congenitally  deaf. 

In  the  fourth  class,  where  31.78  per  cent  of  the  children  are 
congenitally  deaf,  all  the  parents  in  the  52  marriages,  with  151 
children,  are  congenitally  deaf. 

While  too  few  to  give  quantitative  results,  these  statistics  prove 
that  it  is  the  congenital  and  not  the  adventitious  deafness  which 
descendants  have  to  fear. 

Careful  study  of  the  history  of  these  pupils  of  the  asylums 
shows  that  the  relatives  of  deaf  persons  must  also  be  taken  into 
consideration,  and  that  statistical  data  which  do  not  include  this 
factor  are  inadequate  as  a  basis  for  generalization  on  inheritance. 
Of  the  26  families  in  which  both  parents  are  deaf  and  have  con- 
genitally deaf  children,  there  are  5  families  in  which  one  of  the 
parents  has  a  deaf  parent,  17  families  in  which  both  parents  have 
deaf  relatives  of  the  same  generation,  4  in  which  one  parent  has 
deaf  relatives  of  the  same  generation,  and  only  5  in  which  no  deaf 
relatives  of  the  same  generation  are  reported. 

Of  the  26  families  in  which  both  parents  are  congenitally  deaf 
and  have  hearing  children  only,  there  is  not  one  parent,  so  far  as 


G ALTON  AND  STATISTICAL   STUDY  OF  INHERITANCE     1/5 

reported,  with  a  deaf  parent;  there  are  12  families  in  which  both 
parents  have  deaf  relatives  of  the  same  generation  ;  1 1  in  which 
one  parent  has  deaf  relatives  of  the  same  generation  ;  and  3  in 
which  neither  parent  has  deaf  relatives  of  the  same  generation. 

This  illustration  proves  that  the  origin  of  an  individual  pecu- 
liarity has  much  to  do  with  the  question  of  its  inheritance,  and  that 
we  cannot  be  sure  that  statistical  data  illustrate  inheritance  unless 
we  can  separate  the  phenomena  of  ancestry  from  those  of  nurture. 

Furthermore,  in  order  to  prove  that  children  always  revert  to 
the  mean  or  type  of  the  race,  and  are  on  the  average  more  medi- 
ocre than  their  parents,  we  must  prove  that  this  is  the  case  when 
both  parents  have  the  same  inherited  peculiarity.  Galton  shows 
that  this  is  true  of  the  stature  of  children  both  whose  parents 
were  tall  or  both  short,  but  he  has  not  shown  that  it  is  true 
when  the  peculiarity  in  the  stature  of  both  parents  is  the  same 
inherited  peculiarity.  He  points  out  that  stature  may  be  affected 
by  diversity  in  the  thickness  of  more  than  one  hundred  bodily 
parts,  and  it  is  plain  that  if  the  extra  height  of  a  tall  father  is 
due,  for  example,  to  a  long  femur,  the  chances  are  a  hundred  to 
one  that  the  femur  of  the  tall  mother  is  normal,  and  that  her 
extra  height  is  due  to  some  other  peculiarity  —  thick  intervertebral 
bodies,  for  example. 

There  is  statistical  evidence  from  other  sources  to  show  that 
if  both  the  parents  have  long  femurs  and  have  brothers  and  sis- 
ters with  long  femurs,  the  children,  instead  of  reverting  to  medi- 
ocrity, may  be  expected  to  have,  on  the  average,  femurs  very 
much  above  the  mean,  and  that  some  of  them  may  have  them 
longer  than  either  parent. 

Many  facts  in  our  stock  of  information  regarding  domesticated 
animals  and  cultivated  plants  show  that  hereditary  peculiarities 
are  often  very  persistent  independently  of  selection,  and  the  expe- 
rience of  all  breeders  shows  that  this  tendency  is  greatly  intensified 
when  both  parents  have  the  same  inherited  peculiarity.  Not  only  is 
this  the  case,  but  it  may  be  proved  by  many  observations  that  the 
normal  or  type  to  which  the  average  children  of  exceptional  parents 
tend  to  revert  may  itself  be  rapidly  modified.  In  proof  of  this 
I  refer  to  the  following  experiments  in  selection  by  Fritz  Miillei; 
("Ein  Zuchtungs-versuch  an  Mais,"  Kosmos,  1886,  2,  I,  p.  22)  :  — 


1/6 


THE  FOUNDATIONS  OF  ZOOLOGY 


Yellow  corn  is  very  variable  in  many  respects.  The  number 
of  rows  of  kernels  on  the  cob  was,  at  the  time  Miiller  made  his 
experiments,  from  8  to  i6;  cobs  with  lo  or  12  rows  being  the 
most  common,  while  one  with  18  or  20  rows  was  very  seldom 
found.  After  searching  through  several  hundred  cobs  he  found 
one  ear  with   18  rows,  but  none  with  more. 

In  1867  he  sowed,  at  different  times,  and  in  such  a  way  as 
to  prevent  crossing,  (i)  seed  from  the  cob  with  18  rows;  (2)  the 
seed  from  the  finest  i6-rowed  ear;  and  (3)  the  seed  from  the 
finest  14-rowed  ear.  In  1868  he  sowed  (i)  seed  from  a  i6-rowed 
ear  which  had  grown  from  a  i6-rowed  ear;  (2)  seed  from  an  18- 
rowed  ear  that  had  grown  from  i6-rowed  seed;  and  (3)  seed 
from  an  i8-rowed  ear  from  i8-rowed  seed.  In  1869  he  sowed 
(i)  seed  from  an  i8-rowed  ear  with  i8-rowed  parents  and  grand- 
parents; (2)  seed  from  a  20-rowed  ear  with  i8-rowed  parents  and 
grandparents;  and  (3)  seed  from  a  22-rowed  ear  from  seed  from 
an  i8-rowed  ear  produced  from  seed  from  a  i6-rowed  ear.  The 
results  are  given  in  the  following  table :  — 


1867 

1868 

1869 

Number   of    rows    on 

16 
16 

16 
18 

18 
18 

18 

18 

16 

cob  from  which  seed 
were  taken. 

14 

16 

18 

18 
18 

18 
20 

18 

22 

Total  number  of  cobs 
produced. 

658 

385 

205 

1789 

262 

460 

2486 

740 

373 

Perc't 

Perc't 

Perc't 

Perc't 

Perc't 

Perc't 

Perc't 

Perc't 

Perc't 

8-rowed  cobs    .'    .     . 

0-3 

.... 

0-5 

0.1 

.... 

.... 

lo-rowed  cobs    . 

14.4 

3-0 

I.O 

1.4 

0.8 

0.2 

0.1 

<   >  •   ■ 

i2-rowed  cobs    . 

48.0 

22.8 

13.0 

22.6 

14-5 

7-8 

6.1 

6.1 

2-7 

14-rowed  cobs    . 

35-6 

48.6 

37-8 

48.5 

46.7 

35-4 

37-3 

28.5 

25-3 

i6-rowed  cobs    . 

3-2 

18.7 

34-5 

22.2 

23-7 

33-8 

41.6 

41.8 

1 8-rowed  cobs    . 

0-5 

6.8 

12.6 

4.9 

12.3 

18.2 

18.6 

20.2 

24.1 

20-rowed  cobs    . 

. . .  ■ 

0.1 

0-3 

0.3 

1.2 

4.4 

3-9 

2.8 

4.8 

22-rowed  cobs    . 

.... 

.... 

0-3 

.... 

0.8 

0.2 

0-5 

0.8 

1.0 

26-rowed  cobs    . 













0-5 

Average     .     . 

12.61 

14.08 

14.9 

14-15 

14-39 

15-52 

15-57 

15-70 

16.15 

It  will  be  seen    from    this   table   that  the    number  of  ears  with 
few  rows  decreases  very  rapidly  in  plants  grown  from  seed  taken 


G ALTON  AND  STATISTICAL  STUDY  OF  INHERITANCE     i// 

from  ears  with  many  rows,  and  that  the  greater  the  number  of 
rows  on  the  ear  from  which  the  seed  is  taken,  the  smaller  is  the 
number  of  ears  produced  with  a  small  number  of  rows.  It  is  also 
plain  that,  as  the  number  of  rows  on  the  ear  from  which  the  seed 
was  taken  increases,  the  number  of  ears  produced  with  a  large 
number  of  rows  increases,  and  that  we  have  in  each  case  a  very- 
considerable  number  of  ears  which  equal  their  parents  and  a  few 
which  excel  them,  even  when  the  parent  seeds  are  far  beyond  the 
maximum  for  all  ordinary  corn.  Fritz  Miiller  says  he  has  never 
under  ordinary  conditions,  except  in  three  instances,  found  an  ear 
with  more  than  i8  rows,  and  Darwin  puts  the  maximum  at  20 
rows  ;  yet  we  have  among  the  children  of  seed  from  a  22-rowed 
ear  no  less  than  4.8  per  cent,  or  18  ears  out  of  373  with  20 
rows,  and  one  ear  out  of  373  with  26  rows,  and  it  will  also  be 
seen  that  the  number  of  children  which  equalled  their  parents 
increases  in  each  case  in  each  successive  generation. 

Thus  the  seed  planted  in  1867  from  an  i8-rowed  ear  produced 
12.6  per  cent  of  i8-rowed  children.  The  i8-rowed  ear  planted 
in  1868  from  an  i8-rowed  parent  produced  18.2  per  cent  of  18- 
rowed  children,  and  the  i8-rowed  seed  planted  in  1869  from  18- 
rowed  parents  and  grandparents  produced  18.6  per  cent  of 
i8-rowed  children.  The  series  is  12.6  per  cent,  18.2  per  cent, 
and  18.6  per  cent.  The  rapid  change  which  took  place  in  the 
"  type  "  after  only  three  years  of  selection  is  well  shown  by  the 
following  table,  which  gives  the  dominant  number  of  ears  at  each 
sowing  and  also  the  percentage  of  ears  which  had  this  number :  — 


1867,  12  rows     . 

. 

•     48% 

1868,  14  rows     .     . 

•     •     35-4% 

1867,  14  rows     . 

. 

.     48.6% 

1869,  14  rows     .     . 

•     •     37-3% 

1868,  14  rows     . 

. 

•     48.5% 

1869,  16  rows     .     . 

•     .     41-6% 

1867,  14  rows     . 

. 

•     38.8% 

1869,  16  rows     .     . 

.     .     41-8% 

The  minimum  for  the  third  generation  is  equal  to  the  mean 
for  the  first ;  the  mean  for  the  third  generation,  16  rows,  is  very 
near  the  maximum  for  ordinary  corn,  and  the  maximum  for  the 
third  generation  is  far  beyond  the  maximum  for  the  grandparents, 
and  much  beyond  the  maximum  for  the  parents. 

No  one  can  dispute  the  well-known  fact  that  this  sort  of  pedi- 
gree selection  for  a  single  point  quickly  grows  less  and   less    cffcc- 

N 


1/8  THE  FOUNDATIONS   OF  ZOOLOGY 

tive,  and  soon  reaches  a  maximum ;  but  this  is  no  proof  of  any 
"  principle  of  organic  stability,"  or  anything  else  except  the  truth 
that  long  ages  of  natural  selection  have  made  the  organism  such 
a  unit  or  coordinated  whole  that  no  great  and  continuous  change 
in  one  feature  is  possible,  unless  it  be  accompanied  by  general 
or  constitutional  change. 

Nor  must  we  forget  that,  in  a  state  of  nature,  selection  is  not 
for  one  feature,  nor  is  it  pedigree  selection,  or  breeding  from  the 
fittest.  It  is  the  extermination  of  the  unfit,  and  unfitness  may 
come  from  the  imperfect  coordination  of  the  whole,  or  from 
defect  in  any  quality  whatever. 

It  is  undoubtedly  true  that  many  of  our  domesticated  races 
can  be  proved  to  have  arisen  as  "sports,"  and  that  no  great 
change  of  type  can  be  effected,  by  the  victJiods  of  the  breeder, 
without  sports ;  but  there  seem  to  be  both  evidence  and  theoreti- 
cal ground  for  holding  that,  in  this  particular,  artificial  selection 
gives  no  measure  of  natural  selection. 

It  seems  to  me  that,  notwithstanding  the  great  value  of  Gal- 
ton's  data,  they  fail  to  prove  that  the  "  principle  of  organic 
stability "  owes  its  existence  to  anything  except  past  selection ; 
that  regression  to  mediocrity  occurs  when  ancestry  is  studied 
uncomplicated  by  nurture;  that  the  "mid-parent"  is  anything  else 
than  the  actual  parent;  that  "sports"  are  fundamentally  different 
from  the  ordinary  differences  between  individuals ;  or  that  natural 
selection  is  restricted  to  the  preservation  of  sports. 

Our  tendency  to  believe  that  a  type  is  something  more  real 
and  substantial  than  the  transitory  phenomena  which  exhibit  it,  is 
deeply  rooted  in  our  minds. 

As  the  very  nature  of  this  belief  renders  disproof  of  it  impos- 
sible, we  can  feel  little  surprise  at  its  appearance  and  reappear- 
ance time  after  time  in  the  history  of  thought,  although  science 
is  based  upon  the  well-warranted  opinion  that,  whether  types  are 
real  or  unreal,  we  know  them  only  as  generalizations  or  abstrac- 
tions constructed  by  our  minds  out  of  experience  of  the  orderly 
sequence  of  phenomena. 

In  zoology  and  botany  the  conception  of  species  is  unquestion- 
ably valid  and  justifiable,  and  as  its  most  obvious  characteristic  is 
its  persistency,  as  contrasted  with    the  fleeting   procession    of    eva- 


G ALTON  AND  STATISTICAL  STUDY  OF  INHERITANCE     1 79 

nescent  individuals,  we  cannot  wonder  at  the  vitality  of  the 
belief  that  specific  types  of  life  are  more  real  than  the  individual 
animals,  although  Darwin's  work  has  done  away  with  whatever 
evidence  may  at  one  time  have  seemed  to  support  this  belief. 

To  the  further  question,  whether  specific  types  are  inherent  in 
living  matter  or  external  and  objective  to  it,  Darwin  answers  that 
they  are  both ;  that  they  are  inherent,  insomuch  as  all  their  data, 
or  "events,"  are  properties  of  the  physical  basis  of  life;  but  that 
they  are  external,  inasmuch  as  the  agreement  of  the  "  events " 
with  the  "law  of  frequency  of  error"  is  the  effect  of  the 
environment. 

Biology  is  not  a  closed  science,  and  Darwin's  view  of  the  mat- 
ter is  not  proved  —  possibly  it  is  not  provable;  but  its  great  value 
is  in  the  proof  that  there  is  no  shadow  of  evidence  for  any  other 
view. 

When  embryologists  talk  about  the  doctrine  of  evolution  in 
embryology  as  antagonistic  to  the  doctrine  of  epigenesis ;  when 
biologists  seek  for  the  origin  of  species  in  "  laws  of  variation " 
which  are  not  the  outcome  of  selection ;  when  they  talk  about  a 
"  principle  of  organic  stability "  which  does  not  owe  its  origin  to 
the  same  agency,  —  it  seems  to  me  that  they  fail  to  grasp  the  sig- 
nificance of  Darwin's  work,  and  that  they  are  wandering  from  the 
only  path  in  which  we  can  have  any  well-grounded  hope  for  prog- 
ress—  the  path  which  takes  its  departure  from  that  conception 
of  specific  types  which  leads  us  to  seek  for  the  origin  of  the 
"events"  which  exhibit  the  type  in  the  physical  properuies  of 
living  matter,  and  to  seek  in  the  order  of  nature  external  to  the 
organism  for  the  origin  of  the  "law  of  error,"  which  forms  a 
type  out  of  these  events. 


i 


LECTURE    VIII 

DARWIN,   AND   THE    ORIGIN    OF   SPECIES 


"The  idols  of  the  market  are  the  most  troublesome  of  all;  those,  namely,  which  have 
entwined  themselves  around  the  understanding  from  the  associations  of  words  and  names. 

"There  arises  from  a  bad  and  unapt  formation  of  words  a  wonderful  obstruction  to  the 
mind." —  Bacon. 

"  Language  being  accommodated  to  the  preenotions  of  men  and  the  uses  of  life,  it  is 
difficult  to  express  therein  the  precise  truth  of  things,  which  are  so  contrary  to  our  prK- 
notions.  But  to  one  of  due  attention,  and  who  makes  my  words  an  occasion  of  his  own 
thinking,  I  conceive  the  whole  to  be  very  intelligible  ;  and  when  it  is  rightly  understood  I 
scarce  doubt  but  it  will  b<;  assented  to."  —  Berkeley. 


LECTURE   VIII 

DARWIN,  AND  THE  ORIGIN  OF  SPECIES 

The  aim  of  this  lecture  is  to  show  that  most  of  the  post-Dar- 
winian criticism  of  natural  selection  might  have  been  avoided  if 
Darwin  and  Wallace,  and  they  who  have  come  after,  had  not  been 
unconsciously  led  to  make  use  of  words  and  forms  which  have 
since  outlived  their  meaning. 

I  do  not  allude  to  the  assertion  so  often  made  that  natural  selec- 
tion personifies  nature,  and  attributes  to  it  the  power  of  deliberate 
choice  ;  for  no  one  who  thinks  for  himself  can  attach  any  such 
meaning  to  Darwin's  words,  or  be  misled  by  them. 

The  Duke  of  Argyll,  indeed,  says  Darwin's  work  is  "  essentially 
the  image  of  mechanical  necessity  concealed  under  the  clothes  and 
parading  in  the  mask  of  mental  purpose,"  since  natural  selection 
"personifies  an  abstraction."  If  the  roses  in  a  garden  differ  among 
themselves  in  power  to  resist  cold,  and  the  more  tender  ones  are 
found  dead  after  a  hard  winter,  the  Duke  of  Argyll  may,  if  he 
sees  fit,  charge  him  who  says  the  toughest  ones  have  been  selected, 
with  infantile  belief  in  the  personal  agency  of  Jack  Frost,  but  I 
cannot  believe  thoughtful  men  will  support  him. 

If  living  things  differ  among  themselves,  and  if  those  which 
survive  the  struggle  for  existence  are  the  ones  which  might  have 
been  expected  to  survive,  natural  selection  is  a  fact;  and  while 
opinions  as  to  the  value  of  this  fact  may  differ,  the  name  we  call 
it  by  matters  little. 

One  of  the  most  familiar  criticisms  of  natural  selection  is  that, 
since  it  does  not  produce,  but  only  preserves,  the  fitness  which 
exists,  it  does  not  show  why  there  should  be  any  fit  to  survive,  but 
only  why  the  unfit  are  exterminated. 

"Natural  selection,"  says  Darwin  ("Origin,"  p.  75),  "acts  only 

183 


1 84  THE  FOUNDATIONS  OF  ZOOLOGY 

by  the  preservation  and  accumulation  of  small  inherited  modifica- 
tions, each  profitable  to  the  preserved  being."  This  has  seemed, 
and  still  seems,  to  many,  a  valid  reason  for  questioning  its  value 
as  a  scientific  explanation  of  the  origin  of  species ;  although  no 
one  who  makes  Darwin's  words  an  occasion  of  his  own  thinking 
need  be  perplexed  by  this  criticism.  If  peas  are  rolled  down  an 
inclined  board,  the  largest  go  fastest,  the  smallest  slowest,  and  the 
round  ones  go  straight  to  the  bottom,  while  the  irregular  ones  run 
off  the  sides.  What  if  one  were  to  assert  that  this  device  can  have 
no  value  as  a  means  for  sorting  peas  until  we  know  what  makes 
one  pea  large  and  another  small,  one  round  and  another  irregular } 
Yet  this  is,  in  effect,  asserted  by  those  who  declare  that  natural 
selection  has  no  value  as  an  explanation  of  the  origin  of  species, 
because  it  does  jiot  show  why  there  should  be  anything  useful  to 
select.  Without  knowing  why  one  horse  is  more  fleet  than  another, 
or  even  why  horses  exist,  breeders  have  increased  the  speed  of 
horses  by  breeding  from  the  most  fleet;  just  as  a  pack  of  wolves 
may  increase  it  in  nature  by  destroying,  generation  after  genera- 
tion, all  the  horses  they  can  run  down.  If  at  every  stage  in  the 
ancestry  of  horses  there  has  been  need  for  greater  speed,  natural 
selection  accounts  for  the  whole  history  of  this  power,  and  even 
for  the  first  vague  beginnings  of  locomotion  in  sedentary  or  float- 
ing animals,  which  may  have  found  shelter  from  their  enemies, 
or  more  abundant  food,  by  those  slight  changes  of  place  which 
may,  at  first,  have  been  the  incidental  result  of  changes  of 
shape. 

While  it  is  obvious  that  a  useful  quality  must  exist  before  it 
can  be  useful,  and  before  it  can  be  influenced  by  selection,  and 
while  no  Darwinian  holds  natural  selection  to  be  an  ultimate  ex- 
planation of  fitness,  all  admit  that  horses  do  differ  among  them- 
selves in  speed,  and  that  each  may  reasonably  be  expected  to  be 
more  like  its  parents  in  speed  than  like  a  horse  selected  at  random. 
As  no  one  disputes  the  existence  of  these  prerequisites  to  selec- 
tion, the  statement  that  selection  could  not  act  unless  they  existed 
is  childish. 

I  have  tried  to  show,  page  178,  that  the  work  of  Darwin  and 
Wallace  teaches  that  the  only  path  in  which  we  can  have  any  well- 
founded  hope  of  progress  in  the  explanation  of  the  origin  of  species 


DARWIN,   AND    THE  ORIGIN  OF  SPECIES  1 85 

is  that  which  takes  its  departure  from  that  conception  of  specific 
adaptive  types,  which  leads  us  to  seek  the  origin  of  the  "  events  " 
that  exhibit  the  type  in  the  physical  properties  of  living  matter, 
and  to  seek  the  origin  of  the  statistical  "  law  of  error  "  which  forms 
an  adaptive  type  out  of  these  events  in  the  order  of  external  nature. 
I  shall  now  try  to  illustrate  the  way  in  which  the  order  of  nature 
forms  adaptive  types,  or  zoological  species,  out  of  the  events  which 
are  afforded  by  the  properties  of  living  beings. 

•  While  no  one  doubts  that  the  paths  of  all  the  drops  in  a  shower 
of  rain  might  have  been  predicted  from  mechanical  data,  one  who 
knows  none  of  these  data  may,  by  an  umbrella,  make  determinate 
the  paths  of  all  the  drops  which  immediately  concern  him.  In  statis- 
tical language  we  may  say  that,  even  if  we  know  nothing  of  the 
causes  of  the  events,  we  may  make  an  adaptive  type  out  of  them  by 
means  of  an  umbrella ;  and  if  we  move  the  umbrella  to  another 
place,  we  may  make  a  new  type,  identical  in  adaptive  value,  out 
of  a  different  set  of  events ;  for  the  causes  of  the  events  have 
nothing  to  do  with  the  use  to  which  we  put  them,  except  in  this, 
that  we  could  not  use  them  unless  they  occurred. 

If  before  a  long  line  of  machine  guns,  scattering  bullets  to  all 
quarters  of  the  field,  we  set  up  a  target,  exhaustive  knowledge  of 
machine  guns  might  enable  one  to  say  how  many  balls  will  strike 
it  in  a  given  time,  and  how  they  will  be  distributed,  but,  as  we  use 
words,  we  say  certain  balls  chance  to  hit,  for  the  target  does  not 
affect  in  any  way  the  course  by  which  a  ball  reaches  it.  If  we 
now  put  before  the  target  a  screen  with  a  hole  in  it,  no  one  safely 
behind  the  screen  would  wish  to  show  his  face  at  the  hole  incon- 
siderately, since,  so  far  as  it  affects  him,  the  course  of  the  balls  which 
concern  him  has  been  made  determinate. 

Now  imagine  an  unlimited  series  of  similar  screens  set  in  line, 
each  within  range  of  the  next,  and  suppose,  furthermore,  that  while 
each  ball  that  hits  a  screen  drops  and  is  lost ;  each  one  that  goes 
through  a  hole  grows  into  a  new  machine  gun.  No  two  objects, 
natural  or  artificial,  are  exactly  alike,  and  among  the  original 
machine  guns  some  would  put  more  balls  through  the  first 
screen,  and  have  more  descendants  than  others,  even  if  they 
had  been  set,  one  after  another,  in  the  same  place  before  the 
target. 


1 86  THE  FOUNDATIONS   OF  ZOOLOGY 

If  we  suppose  that  while  the  guns  in  each  generation  differ  among 
themselves  like  the  original  guns,  each  is  more  likely  than  a  gun 
taken  at  random  to  resemble  its  parent,  is  it  not  clear  that  if  the 
guns  in  each  generation  and  the  screens  in  the  series  are  both 
innumerable,  the  ultimate  outcome  of  this  survival  of  the  fittest 
will  be  the  production  of  a  race  of  guns  adapted  for  sending  their 
balls  through  the  holes  in  this  particular  series  of  screens,  and 
that  if  another  series  of  screens  arranged  in  a  different  line  or  of 
a  different  size  or  shape  were  set  up,  the  guns  in  later  generations 
would  become  adapted  for  sending  their  bullets  through  them  ? 
It  is  not  necessary  for  us  to  know  anything  about  the  mechanism 
of  guns,  or  the  reason  why  they  differ  among  themselves,  or  any 
data  which  might  enable  us  to  predict  the  paths  of  the  bullets, 
in  order  to  see  that  this  result  may  be  expected  to  follow,  in 
course  of  nature,  if  only  the  trials  be  innumerable ;  if  all  the  balls 
which  fail  to  go  through  a  hole  are  counted  out,  and  if  each  gun 
is,  on  the  average,  more  like  its  parent  than  a  gun  selected  at 
random. 

Each  discharge  of  a  bullet  is  an  event ;  the  race  of  guns  adapted 
for  driving  the  bullets  through  the  holes  is  an  adaptive  type,  and 
the  series  of  screens  is  the  equivalent  of  those  conditions  of  life 
which,  in  course  of  nature,  form  a  zoological  type,  or  species,  out  of 
the  events  which  the  infinite  diversity  among  living  things  affords. 
I  have  used  the  illustration  as  the  simplest  way  to  show  the  error 
of  the  opinion  that  natural  selection  does  not  account  for  the  origin 
of  species  unless  the  differences  between  individuals  are  adaptive 
prior  to  selection  ;  for  it  is  plain  that,  in  our  illustration,  the  result 
is  independent  of  the  nature  of  the  projectiles,  and  equally  inde- 
pendent of  the  mechanism  by  which  they  are  propelled,  since  our 
reason  for  expecting  the  result  would  be  the  same  even  if  they  were 
unknown  projectiles  propelled  by  unknown  means.  It  is  also  clear 
that  one  who  witnessed  the  process  from  the  far  end,  through  the 
holes  in  the  targets,  might  suppose  that  the  course  of  adaptive 
modification  had  been  directed,  from  behind,  to  a  definite  end,  since 
none  of  the  balls  that  failed  to  go  through  the  holes  would  be 
visible  from  this  point  of  view ;  nor  would  the  discovery  of  fossil 
machine  guns  do  much  to  correct  this  error;  for  the  difference 
between  the  exterminated  guns  and  the  survivors  in  the  same  gen- 


DARWIN,   AND    THE  ORIGIN  OF  SPECIES  1 8/ 

eration  would  be  so  slight  as  to  be  unrecognizable  except  by  actual 
trial. 

A  living  thing  is  a  being  which  responds  to  the  stimulus  of 
one  event  in  such  a  way  as  to  adjust  its  actions  to  other  events 
of  which  the  stimulus  is  the  sign,  and  as  all  that  have  not  thus 
responded  have  been  exterminated  in  the  struggle  for  existence,  the 
adjustment  of  the  survivors  is  no  more  than  might  have  been 
expected. 

Natural  selection  seems  to  me  a  strictly  scientific  explanation 
of  the  fitness  of  living  things,  and  they  who  assert  that  it  is  inade- 
quate because  it  fails  to  show  why  beneficial  response  should  ever 
follow  a  stimulus,  and  thus  furnish  fitness  to  be  selected,  must 
remember  that  all  science  is  inadequate  to  exactly  the  same  degree ; 
for  in  no  case  does  science  tell  us  why  natural  phenomena  do 
occur  in  order,  although  it  does  tell  what  order  we  may  reasonably 
expect. 

If  we  find  in  nature  no  reason  why  extended  things  should 
have  weight,  except  that  the  fact  is  so,  need  we  wonder  if  we 
fail  to  discover  any  ultimate  or  final  reason  why  sensitive  things 
should  respond,  for  does  not  every  scientific  explanation  rest 
upon  something  which  is  granted  even  if  unexplained } 

"  It  passeth  with  many,  I  know  not  how,  that  mechanical 
principles  give  a  clear  solution  of  the  phenomena.  .  .  .  But, 
things  rightly  considered,  perhaps  it  will  be  found  not  to  solve 
any  phenomena  at  all." 

They  who  challenge  the  sufficiency  of  natural  selection,  because 
it  does  not  show  why  there  should  be  any  fitness  to  select,  must 
find  all  science  equally  inadequate;  although  the  common  verdict 
of  mankind  is  that  scientific  knowledge  is  very  adequate  and  suf- 
ficient for  all  the  practical  needs  of  living  beings ;  even  if  it  does 
fail  to  show  us  in  nature  any  efficient  cause  for  any  phenomenon 
at  all. 

The  task  which  faced  Darwin  when  the  "  Origin  of  Species  " 
was  written,  was  to  convince  those  who  deny  that  species  are 
mutable.  At  the  present  day,  when  all  naturalists  admit  this, 
many  question  the  adequacy  of  natural  selection  as  an  explanation 
of  the  origin  of  species.  Now  the  way  of  presenting  the  argu- 
ment, and  the  choice  of  words,  which    are   best   adapted    for   con- 


1 88  THE  FOUNDATIONS   OF  ZOOLOGY 

vincing  those  who  deny  the  mutability  of  species,  may  not  be,  in 
fact  cannot  be  expected  to  be,  the  best  for  demonstrating  the 
vahie  of  natural  selection  to  those  who  admit  that  species  are 
mutable. 

Before  Darwin's  day  most  systematic  zoologists  and  botanists 
believed  that  certain  characteristics  of  each  living  being  have 
"  specific  value "  while  others  are  "  varietal."  The  question  how 
you  are  to  tell,  from  a  single  specimen,  what  characters  are 
specific  and  what  varietal  gave  rise  to  interminable  disputes,  but 
there  was  general  agreement  that  the  distinction  exists  in  nature, 
and  that  very  dreadful  consequences  would  attend  doubt  of  its 
reality. 

Specific  characters,  and  those  of  generic  or  ordinal  value  as 
well,  were  held  to  be  immutable ;  and  while  the  individual  mem- 
bers of  a  species  were  admitted  to  differ  among  themselves,  or 
to  "  vary,"  in  characters  which  are  not  of  specific,  or  more  than 
specific  value,  all  were  held  to  be  exactly  alike  in  their  specific 
characters,  and  also  in  all  characters  of  generic  or  of  still  higher 
taxonomic  importance. 

As  an  exact  science  the  Taxonomy  of  the  last  century  is  as 
extinct  as  the  dodo,  for  its  very  name  is  well-nigh  forgotten ;  and 
since  few  zoologists  of  the  new  school  carry  their  so-called  bibli- 
ographical researches  into  the  dust-covered  books  in  which  it  is 
entombed  on  the  top  shelves  of  old  libraries,  they  fail  to  discover 
that  the  words  variety,  vary,  and  variation  were  technical  terms 
when  the  "  Origin  of  Species "  was  written. 

Of  the  twenty  years  and  more  which  were  devoted  to  the  prepa- 
ration of  the  book,  many  were  spent  in  the  study  of  domesti- 
cated animals  and  cultivated  plants,  and  in  the  comparison  and 
measurement  of  each  species  part  by  part.  Darwin  devoted  him- 
self to  this  work  until  he  had  obtained  conclusive  proof  that 
specific  characters  are  as  mutable  as  varietal  characters,  and  until 
he  had  shown  that  there  is  no  organ  or  structure  or  marking 
or  measurement  or  habit  or  instinct  which  may  not  exhibit 
diversity  if  many  representatives  of  the  species  are  carefully 
compared. 

These  observations  and  measurements,  which  were  afterwards 
published  as  a  book  under  the  title  of  "The  Variation  of  Animals 


DARWIN-,   AND   THE  ORIGIN  OF  SPECIES  1 89 

and  Plants  under  Domestication,"  firmly  planted  the  word  vari- 
ation in  the  literature  of  a  generation  which  has  forgotten  that  it 
is  a  technical  term;  although  any  one  who  will  make  the  attempt 
will  find  few  places,  in  this  book,  or  in  the  "Origin  of  Species," 
or  in  the  writings  of  Wallace,  where  diversity  may  not  be  sub- 
stituted for  variation  without  changing  the  meaning;  and  although 
Darwin  has  himself  defined  the  word  in  the  introduction  to  this 
work  ("Animals  and  Plants,"  Amer.  ed.,  p.  14)  in  the  promise 
that  "  in  a  second  work  I  shall  discuss  the  variability  of  organic 
beings  in  a  state  of  nature,  namely,  the  individual  differences  pre- 
sented by  animals  and  plants,  and  those  slightly  greater  and 
generally  inherited  differences  which  are  ranked  by  naturalists 
as  varieties  or  geographical  races."  "  We  shall  see,"  he  says, 
"  how  difficult,  or  rather  impossible,  it  often  is,  to  distinguish 
between  races  and  sub-species,  as  the  less  well-marked  forms 
have  sometimes  been  denominated,  and  again  between  sub-species 
and  species." 

Now,  as  words  are  commonly  used,  the  great  practical  differ- 
ence between  diversity  and  variation  in  this;  that,  while  all  admit 
the  infinite  diversity  of  nature,  variation  is  a  dynamical  *  change, 
and  is  not  held  to  be  accounted  for  until  a  physical  cause  of  the 
change  has  been  discovered. 

I  cannot  believe  any  one  would  have  thought  that  natural 
selection  fails  to  account  for  the  origin  of  species  until  we 
discover  some  other  explanation  of  the  fitness  of  the  varia- 
tions which  are  selected,  if  Darwin  and  Wallace  had  not  used 
the  word  with  this  technical  meaning;  for  we  may  admit  that 
living  things  do  not  differ  from  each  other  without  cause,  with- 
out admitting  that  the  physical  causes  of  this  diversity  are 
adaptive. 

The  objection  to  natural  selection  which  has  thus  arisen  is 
often  formulated  as  an  assertion  that  since  natural  selection  does 
not  produce,  but  only  preserves,  the  variations  which  are  fittest, 
it  accounts  for  nothing  in  itself,  since  the  real  explanation  of  the 
origin  of  species  is  to  be  sought  in  the  "laws  of  variation"  or 
"causes  of  variation,"  which  must,  it  is  said,  supply  the  raw 
material  for  selection  before  this  can  be  selected. 

As  it  is  self-evident    that    natural    selection    originates  nothing. 


190  THE  FOUNDATIONS  OF  ZOOLOGY 

this  objection  is  a  very  subtle  one.  In  one  or  another  of  its  many 
forms  it  has  afforded  the  basis  for  most  of  the  post-Darwinian  criti- 
cism of  Darwin's  work;  nor  do  I  hope  to  demonstrate  its  error, 
at  this  late  day,  to  any  who  have  mastered  the  first  four  chapters 
of  the  "Origin"  without  conviction;  for  he  who  does  not  succeed  in 
making  Darwin's  clear  and  simple  words  an  occasion  of  his  own 
thinking,  reminds  one  of  the  five  brethren  of  a  certain  rich  man 
mentioned  in  history. 

If  the  individuals  which,  in  each  generation,  make  up  a  species 
differ  among  themselves  in  innumerable  characters,  and  yet  tend, 
on  the  whole,  to  be  more  like  their  parents  than  individuals  taken 
at  random,  and  if,  furthermore,  the  rate  of  increase  of  all  living 
things  tends  to  outrun  the  means  of  support,  the  survival  of  the 
fittest,  and  the  gradual  perfection  of  the  adjustments  of  each  species 
are  no  more  than  might  have  been  expected. 

Fifteen  years  before  he  published  the  "Origin,"  Darwin  wrote  to 
Hooker  as  follows :  "  Heaven  forfend  me  from  Lamarck  nonsense, 
but  I  think  I  have  found  out  the  simple  way  in  which  species 
become  adapted  to  various  ends "  :  although  the  assertion  that 
natural  selection  is  dependent  upon  laivs  of  variation,  or  causes  of 
variation,  for  its  raw  material  denies,  explicitly  or  by  implication, 
that  he  had  found  out,  in  natural  selection,  the  simple  means  by 
which  species  become  adapted  to  the  conditions  of  their  life,  for 
we  must  look  to  these  laius  or  causes  for  the  real  explanation  of 
the  usefulness  of  the  properties  which  natural  selection  picks  out 
and  accumulates. 

It  must  not  be  supposed  that  the  only  advocates  of  this  opinion 
are  natural  theologians  who  are  so  short-sighted  as  to  fear  that,  if 
natural  selection  were  admitted  to  be  an  explanation  of  the  fitness 
of  livin'::  things,  this  might  show  that  their  fitness  is  not  real  fit- 
ness ;  for  while  it  has  been  made  much  of  in  what  has  been 
supposed  to  be  the  interest  of  natural  theology,  it  has  also  been 
held  by  men  of  science  who  seek  no  alliance  with  the  natural 
theologians.  In  fact,  one  modern  writer  who  tells  us  that  this 
reasoning  has  no  value  when  used  in  their  interest  (Romanes, 
"Darwin  and  after  Darwin,"  I.,  p.  336),  himself  makes  use  of  it 
a  few  pages  further  on  in  the  supposed  interest  of  science ; 
for   he   tells    us   that    if    the    Lamarckian    principles    are    in    any 


DARWIN,   AND    THE  ORIGIN  OF  SPECIES  191 

degree  operative  at  all,  the  great  function  of  these  principles  must 
be  that  of  supplying  to  natural  selection  the  incipient  stages  of 
adaptive  modification  in  all  cases,  where,  but  for  this  agency,  there 
would  be  nothing  of  the  kind  to  select. 

I  hope  to  show  that  formidable  as  this  criticism  appears,  and 
grave  as  the  difficulty  has  seemed  to  many  able  thinkers,  it  is, 
after  all,  verbal  in  origin ;  and  that  they  who  believe  that  natu- 
ral selection  fails  to  account  for  the  origin  of  species  until  some 
other  source  for  the  incipient  stages  of  adaptive  modification  has 
been  discovered  are  misled  by  words ;  for  no  Darwinian  supposes 
that  selection  produces  either  the  incipient  or  final  stages  of  any 
modification,  adaptive  or  otherwise,  although  all  are  aware  that 
there  is,  unfortunately,  no  incompatibility  between  the  system  of 
things  and  injurious  modification. 

Darwin  very  wisely  made  much  of  the  history  of  domesticated 
animals  and  cultivated  plants,  for  many  reasons ;  and,  as  I  believe, 
for  this  among  others :  that  since  the  use  or  purpose  of  fancy 
breeds  is  the  gratification  of  the  whim  of  the  breeder,  or  conformity 
to  the  arbitrary  rules  of  fanciers'  clubs,  good  common  sense  must 
decline  serious  consideration  of  the  belief  that  the  causes  of  varia- 
tion stand  in  any  relation,  incipient  or  otherwise,  to  this  purpose, 
except  so  far  as  all  nature  may  be  intended. 

Darwin  writes  to  Asa  Gray:  "You  lead  me  to  infer  that  you 
believe  that  variation  has  been  carried  along  certain  beneficial  lines. 
I  cannot  believe  this:  and  I  think  you  would  have  to  believe  that 
the  tail  of  the  Fantail  was  led  to  vary  in  the  number  and  direction 
of  its  feathers  in  order  to  gratify  the  caprice  of  a  few  men."  Few, 
even  among  those  who  believe  that  all  nature  bears  witness  to 
intention,  will  hold  it  good  common  sense  to  expect  to  discover  any 
natural  laws,  or  causes  of  variation,  competent  to  adapt  pigeons  to 
the  arbitrary  rules  of  pigeon  clubs;  for  while  we  may  be  unable 
to  believe  that  fanciers  can  bring  about  any  change  which  a  suf- 
ficient knowledge  of  the  nature  of  pigeons  might  not  have  led  us 
to  expect,  I  cannot  imagine  how  this  nature,  or  the  history  of  its 
origin,  can  be  thought  to  stand,  prior  to  selection,  in  any  specific 
adjustment  to  the  caprice  of  pigeon-fanciers;  for  we  are  much  more 
likely  to  find  the  physical  causes  of  this  adjustment  in  the  mechan- 
ism of  the  breeders'  structure  than  to  find  it  in  the  nature  of  pigeons. 


192  THE  FOUNDATIONS   OF  ZOOLOGY 

The  evidence  that  man  has  produced  all  the  fancy  breeds  of 
pigeons  from  a  single  wild  species  is  admitted  to  be  satisfactory ;  and 
if  these  fancy  breeds  differ  among  themselves  as  much,  and  under 
continued  selection  keep  as  true  to  their  kind  as  wild  species, 
it  seems  clear  that  we  need  not  call  the  causes  of  variation  to  the 
aid  of  natural  selection  to  account  for  the  origin  of  the  various 
species  of  wild  pigeons  from  a  common  stock.  Now  the  evidence 
that  these  fancy  breeds  do  thus  resemble  wild  species,  as  it  is 
summarized  by  Darwin,  in  the  first  chapters  of  the  "  Origin,"  is  as 
convincing  as  it  is  familiar,  and  there  would  be  no  need  to  refer  to 
it  here,  did  not  the  strange  impression  prevail  that  selection  can 
accomplish  nothing  unless  some  other  source  of  adaptive  modifica- 
tion furnish  the  raw  material  to  be  selected. 

Of  domesticated  pigeons  Darwin  says:  "The  diversity  of  the 
breeds  is  something  astonishing.  Compare  the  English  carrier 
and  the  short-faced  tumbler,  and  see  the  wonderful  difference  in 
their  beaks  entailing  corresponding  differences  in  their  skulls. 

"  The  carrier,  more  especially  the  male  bird,  is  also  remarkable 
for  the  wonderful  development  of  the  carunculations  about  the 
head;  and  this  is  accompanied  by  greatly  elongated  eyelids,  very 
large  external  orifices  to  the  nostrils,  and  a  wide  gape  of  mouth. 
The  short-faced  tumbler  has  a  beak  in  outline  almost  like  that  of 
a  finch  ;  and  the  common  tumbler  has  the  singular  inherited  habit 
of  flying  at  a  great  height  in  a  compact  flock,  and  tumbling  in 
the  air  head  over  heels. 

"  The  runt  is  a  bird  of  great  size,  with  very  long,  massive  beak 
and  large  feet ;  some  of  the  sub-breeds  of  runts  have  very  long 
necks,  others  very  long  wings  and  tails,  others  very  short  tails. 
The  barb  is  allied  to  the  carrier,  but,  instead  of  a  long  beak,  has 
a  very  short  and  broad  one.  The  pouter  has  a  much  elongated 
body,  wings,  and  legs ;  and  its  enormously  developed  crop,  which 
it  glories  in  inflating,  may  well  excite  astonishment  and  even 
laughter.  The  turbit  has  a  short  and  conical  beak,  with  a  line 
of  reversed  feathers  down  the  breast;  and  it  has  the  habit  of 
continually  expanding,  slightly,  the  upper  part  of  the  oesophagus. 
The  Jacobin  has  the  feathers  so  much  reversed  along  the  back 
of  the  neck  that  they  form  a  hood ;  and  it  has,  proportionally  to 
its    size,    elongated    wing    and   tail    feathers.      The   trumpeter   and 


DARWIN,  AND   THE  ORIGIN  OF  SPECIES  1 93 

laugher,  as  their  names  express,  utter  a  very  different  coo  from 
the  other  breeds.  The  fantail  has  thirty  or  even  forty  tail  feathers 
instead  of  twelve  or  fourteen, — the  normal  number  in  all  the 
members  of  the  great  pigeon  family  ;  these  feathers  are  kept  ex- 
panded, and  are  carried  so  erect,  that  in  good  birds  the  head  and 
tail  touch  :  the  oil-gland  is  quite  aborted.  Several  other  less  dis- 
tinct breeds  might  be  specified. 

"  In  the  skeletons  of  the  several  breeds,  the  development  of 
the  bones  of  the  face  in  length  and  breadth  and  curvature  differs 
enormously.  The  shape  as  well  as  the  breadth  and  length  of 
the  ramus  of  the  lower  jaw  varies  in  a  highly  remarkable  manner. 
The  caudal  and  sacral  vertebrae  vary  in  number,  as  does  the  num- 
ber of  the  ribs,  together  with  their  relative  breadth  and  the  pres- 
ence of  processes.  The  shape  and  size  of  the  apertures  in  the 
sternum  are  highly  variable ;  so  is  the  degree  of  divergence  and 
relative  size  of  the  two  arms  of  the  furcula.  The  proportional 
width  of  the  gape  of  the  mouth,  the  proportional  length  of  the 
eyelids,  of  the  orifice  of  the  nostrils,  of  the  tongue  (not  always 
in  strict  correlation  to  the  length  of  the  beak),  the  size  of  the 
crop  and  of  the  upper  part  of  the  oesophagus ;  the  development 
and  abortion  of  the  oil-glands ;  the  relative  length  of  the  wing 
and  tail  to  each  other  and  to  the  body ;  the  relative  length  of 
the  leg  and  foot,  the  number  of  scutellas  on  the  toes,  —  are  all 
points  of  structure  which  are  variable.  The  period  at  which  the 
perfect  plumage  is  acquired  varies,  as  does  the  state  of  the  down 
with  which  the  nestling  birds  are  clothed  when  hatched.  The 
shape  and  size  of  the  eggs  vary.  The  manner  of  flight,  and  in 
some  breeds  the  voice  and  disposition,  differ  remarkably.  Lastly, 
in  certain  breeds  the  males  and  females  have  come  to  differ  in  a 
slight  degree  from  each  other.  .  .  .  Altogether,  at  least  a  score  of 
pigeons  might  be  chosen  which,  if  shown  to  an  ornithologist,  and 
he  were  told  that  they  were  wild  birds,  would  certainly  be  ranked 
by  him  as  well-defined  species. 

"  Moreover,  I  do  not  believe  that  any  ornithologist  would,  in 
this  case,  place  the  English  carrier,  the  short-faced  tumbler,  the 
runt,  the  barb,  pouter,  and  fantail  in  the  same  genus;  more  espe- 
cially as  in  each  of  these  breeds  several  truly  inherited  sub-breeds 
or  species,  as  he  would  call  them,  could  be  shown  him." 
o 


194  THE  FOUNDATIONS  OF  ZOOLOGY 

As  fancy  pigeons  are  obviously  adapted  to  the  tastes  of  pigeon- 
fanciers,  and  as  they  owe  their  continued  existence  to  this  adapta- 
tion, in  the  absence  of  which  they  would  have  been  exterminated 
long  ago  by  man,  it  is  hard  to  see  why  any  one  who  knows  what 
changes  man  has  brought  about  by  selection  should  assert  that 
natural  selection  cannot  bring  about  adaptation  unless  it  is  first 
supplied,  from  some  other  source,  with  adaptive  "variations"  in, 
at  the  least,  their  incipient  stages ;  yet  the  incompetency  of  natural 
selection  to  account  for  these  incipient  stages  has  been  made  much 
of,  not  only  by  those  who  believe  that  there  is  no  scientific  or 
natural  explanation  of  these  incipient  stages,  but  also  by  those  who 
attribute  them  to  the  direct  adaptive  action  of  the  conditions  of 
life. 

In  a  book  on  the  "  Genesis  of  Species,"  published  soon  after  the 
"  Origin,"  Mivart  argues  that  even  if  we  admit  that  natural  selection 
is  worthy  of  consideration,  it  can  be  no  explanation  of  any  adapta- 
tion which  is  not  so  useful  that  it  preserves  the  life  of  its  pos- 
sessor ;  and  he  asserts  that  while  perfected  adaptations  may  thus 
preserve  life,  we  cannot  believe  that  the  first  minute  beginnings  of 
adaptation  are  valuable  enough  to  be  preservative. 

Mivart's  argument  has  recently  been  revived,  in  a  somewhat 
modified  form,  by  Romanes  ("Darwin  and  after  Darwin,"  II.),  who 
holds  that  there  are  cases  of  adaptation  where  the  degree  of  use- 
fulness is  so  small  that  we  cannot  believe  it  has  "  selective  value," 
and  that  even  when  useful  reflex  mechanisms  have  been  fully 
formed,  "  it  is  often  beyond  the  power  of  sober  credence  to  believe 
that  they  now  are,  or  ever  can  have  been,  of  selective  value  in  the 
struggle  for  existence." 

Darwin's  work  would  not  have  gained  a  hearing  from  contempo- 
raries if  he  had  not  emphasized  the  results  of  artificial  selection, 
but  I  shall  now  try  to  show  that  this  emphasis  has  led  many  to 
infer,  consciously  or  unconsciously,  that  the  resemblance  between 
natural  selection  and  the  methods  of  the  breeder  is  greater  than  it 
really  is ;  and  that  the  prevalence  of  the  belief  that  selection  cannot 
account  for  the  incipient  stages  of  useful  structures,  and  that  there 
may  be  useful  adaptations  without  selective  value,  is  itself  a  result 
of  Darwin's  choice  of  the  word  selection ;  for  no  one  can  doubt  that 
domesticated   animals  and  cultivated    plants    may  have  characteris- 


DARWIN,   AND    THE  ORIGIN  OF  SPECIES  1 95 

tics  which  fail  to  attract  the  breeder's  notice,  and  that,  so  far  as  he 
is  concerned,  they  may  be  without  "  selective  value." 

The  breeder  may  either  destroy,  promptly  and  utterly,  the  ani- 
mals and  plants  which  he  discards,  or  else,  if  he  have  some  use 
for  them  which  is  independent  of  reproduction,  as  he  has  for 
horses,  he  may  cut  them  off,  at  once  and  forever,  from  all  part 
in  history ;  but  it  is  a  mistake  to  infer  from  this  analogy  that 
extermination  in  the  natural  struggle  for  existence  always  or  even 
generally,  means  sudden  death.  Nothing  could  be  further  from 
the  truth  ;  for  the  total  extinction  of  a  genetic  line  is  usually  slow, 
and  it  may  be  carried  on  for  many  generations  before  it  is  finally 
consummated.  Among  the  terrestrial  animals  and  plants  which 
we  know  best,  sudden  death  during  the  reproductive  period,  when 
the  living  being  is  in  its  prime,  is  not  uncommon,  but  each  organ- 
ism is  so  well  adjusted  to  the  dangers  and  hardships  which  it  may, 
on  the  average,  expect  that  those  which  are  cut  off  completely  from 
posterity  are  exceptional.  "I  must  premise,"  says  Darwin,  "that  I 
use  this  term  struggle  for  existence  in  a  large  and  metaphorical 
sense,  including  dependence  of  one  being  on  another,  and  includ- 
ing (which  is  more  important)  not  only  the  life  of  the  individual, 
but  success  in  leaving  progeny.  ...  A  plant  which  annually  pro- 
duces a  thousand  seeds,  of  which  on  an  average  only  one  comes 
to  maturity,  may  be  said  to  struggle  with  the  plants  of  the  same 
and  other  kinds  which  already  clothe  the  ground."^ 

In  a  long  series  of  generations  all  degrees  of  success  or  failure 
in  rearing  progeny  are  possible,  and  when  we  bear  in  mind  that, 
so  far  as  natural  selection  is  concerned,  success  in  leaving  de- 
scendants is  practically  equivalent  to  survival,  no  matter  what  the 
after-fate  of  the  individual  may  be,  it  is  plain  that  the  process  of 
extinction,  far  from  being  sudden,  may  go  on  so  slowly  as  to  be 
imperceptible,  and  that  there  may  be  many  opportunities  for 
every  useful  quality,  however  slight  its  value,  to  count  for  some- 
thing in  the  result.  "Battle  within  battle  must  be  continually 
recurring  with  varying  success ;  and  yet  in  the  long  run  the  forces 
are  so  nicely  balanced,  that  the  face  of  nature  remains  for  long 
periods  of  time  uniform,  though  assuredly  the  merest  trifle  would 
give  the  victory  to  one  organic  being  over  another."^ 

1 "  Origin,"  p.  50.  ^  "  Origin,"  p.  57. 


196  THE  FOUNDATIONS  OF  ZOOLOGY 

We  must  not  think  of  natural  selection,  after  the  analogy  of 
artificial  selection,  as  a  competitive  examination  in  one  subject, 
where  failure  to  pass  means  loss  of  all  future  chances.  Rather 
must  we  think  of  it  as  a  long  but  indefinite  series  of  examina- 
tions, each  in  innumerable  subjects,  some  of  which  count  for 
much,  others  for  little,  some  for  very  little,  but  all  for  something. 
We  must,  furthermore,  suppose  that  all  candidates  who  do  not 
fail  utterly  may  try  again  and  again,  but  that  each  partial  failure 
may,  if  some  other  candidate  does  better,  diminish,  in  so  far,  the 
chance  for  success  in  future  trials. 

"  Many  different  checks,,  acting  at  different  periods  of  life^ 
and  during  different  seasons  or  years,  probably  come  into  play ; 
but  all  will  concur  in  determining  the  result.  When  we  look  at 
the  plants  and  bushes  clothing  an  entangled  bank,  we  are  tempted 
to  attribute  the  proportional  numbers  and  kinds  to  what  we  call 
chance.  But  how  false  a  view  is  this  !  Every  one  has  heard 
that  when  an  American  forest  is  cut  down,  a  very  different  vege- 
tation springs  up ;  but  it  has  been  observed  that  ancient  Indiaa 
ruins  in  the  southern  United  States,  which  must  formerly  have 
been  cleared  of  trees,  now  display  the  same  beautiful  diversity 
and  proportion  of  kinds  as  in  the  surrounding  virgin  forest. 
What  a  struggle  must  have  gone  on  during  long  centuries  be- 
tween the  several  kinds  of  trees,  each  annually  scattering  its 
seeds  by  the  thousand ;  what  a  war  between  insect  and  insect, 
between  insects,  snails,  and  other  animals,  with  birds  and  beasts 
of  prey,  —  all  striving  to  increase,  all  feeding  on  each  other,  or 
on  the  trees,  their  seeds  and  seedlings,  or  on  the  other  plants 
which  first  clothed  the  ground,  and  thus  checked  the  growth  of 
the  trees !  Throw  up  a  handful  of  feathers,  and  all  fall  to  the 
ground  according  to  definite  laws ;  but  how  simple  is  the  problem 
where  each  shall  fall,  compared  to  the  action  and  reaction  of  the 
innumerable  plants  and  animals  which  have  determined,  in  the 
course  of  centuries,  the  proportional  numbers  and  kinds  of  trees, 
now  growing  on  the  old  Indian  ruins  !  "  ^ 

While  the  breeder  cannot  consciously  and  deliberately  select 
any  peculiarity  which  has  not  enough  selective  value  to  attract 
his   notice,  I    do  not  see  how  any  one  who  is  familiar  with  Dar- 

1  "  Origin,"  p.  58. 


DARWIN',  AND   THE  ORIGIN  OF  SPECIES  1 97 

win's  explanation  of  the  struggle  for  existence  can  believe  any 
useful  structure  will,  in  nature,  be  without  selective  value.  All 
who  grasp  the  meaning  of  the  struggle  for  existence,  which  nature 
exhibits  to  all  who  have  eyes  to  see,  must  agree  with  Darwin 
that,  "  owing  to  this  struggle,  variations,  however  slight,  and  from 
whatever  cause  proceeding,  if  they  be,  in  any  degree,  profitable  to 
the  individuals  of  a  species,  in  their  infinitely  complex  relations 
to  other  organic  beings  and  to  their  physical  conditions  of  life,  will 
tend  to  the  preservation  of  such  individuals."  ^ 

If  the  opinion  that  natural  selection  cannot  account  for  the 
incipient  stages  of  useful  structures  did  not  exhibit  such  vitality, 
there  would  be  no  reason  to  dwell  upon  it ;  but  as  Romanes's 
book  shows  that  thoughtful  men  still  find  it  a  real  difficulty,  I 
shall  now  examine  two  adaptations  which  have  been  used  to  illus- 
trate the  difficulty. 

In  a  chapter  which  he  added  to  the  later  editions  of  the 
"  Origin,"  Darwin  says  that  *'  after  reading  with  care  Mr.  Mivart's 
book,  and  comparing  each  section  with  what  I  have  said  on  the 
same  head,  I  never  before  felt  so  strongly  convinced  of  the  gen- 
eral truth  of  the  conclusions  here  arrived  at";  although  few  illus- 
trations of  the  extent  and  accuracy  and  minuteness  of  Darwin's 
acquaintance  with  nature  are  more  impressive  than  his  demon- 
stration of  the  existence  of  useful  adjustments  similar  to  the 
incipient  stages  in  the  very  adaptations  which  Mivart  uses  to 
prove  his  assertion  that  "  natural  selection  cannot  account  for  the 
incipient  stages  of  useful  structures." 

"The  Greenland  whale,"  says  Darwin,  "is  one  of  the  most  won- 
derful animals  in  the  world,  and  the  baleen,  or  whalebone,  one  of 
its  greatest  peculiarities.  The  baleen  consists  of  a  row,  on  each 
side  of  the  upper  jaw,  of  about  three  hundred  plates  or  laminae, 
which  stand  close  together  transversely  to  the  long  axis  of  the 
mouth.  Within  the  main  row  there  are  some  subsidiary  rows. 
The  extremities  and  inner  margins  of  the  plates  are  frayed  with 
stiff  bristles,  which  clothe  the  whole  gigantic  palate,  and  serve 
to  strain  or  sift  the  water,  and  thus  secure  the  minute  prey  on 
which  these  great  animals  subsist.  The  middle  and  longest 
lamina   in   the   Greenland   whale   is    ten,   twelve,    or    even    fifteen 

^  "  Origin,"  p.  49. 


198  THE  FOUNDATIONS   OF  ZOOLOGY 

feet  in  length ;  but  in  the  different  species  of  Cetaceans  there 
are  gradations  in  length ;  the  middle  lamina  being  in  one  species, 
according  to  Scoresby,  four  feet,  in  another  three,  in  another 
eighteen  inches,  and  in  the  Balcenoptera  rostrata  only  about  nine 
inches  in  length. 

"  With  respect  to  the  baleen,  Mr.  Mivart  remarks  that  if  it 
had  once  attained  such  a  size  atid  development  as  to  be  at  all 
useful,  then  its  preservatioft  and  augmentation  within  serviceable 
limits  woidd  be  promoted  by  natural  selectiofi  alo7ie.  But  how  to 
obtain   the   beginning  of  such  useful  development? 

"  In  answer  it  may  be  asked,  why  should  not  the  early  pro- 
genitors of  the  whales  with  baleen  have  possessed  a  mouth  con- 
structed something  like  the  laminated  beak  of  a  duck  .■*  Ducks, 
like  whales,  subsist  by  sifting  the  mud  and  water ;  and  the  fam- 
ily has  sometimes  been  called  the  Cribratores,  or  sifters.  I  hope 
I  may  not  be  misconstrued  into  saying  that  the  progenitors  of 
whales  did  actually  possess  mouths  laminated  like  the  beak  of  a 
duck.  I  wish  only  to  show  that  this  is  not  incredible,  and  that 
the  immense  plates  of  baleen  in  the  Greenland  whale  might  have 
been  developed  from  such  laminae  by  finely  graduated  steps,  each 
of  service  to  its  possessor, 

"  The  beak  of  a  shoveller-duck  {Spatula  clypeata)  is  a  more 
beautiful  and  complex  structure  than  the  mouth  of  a  whale.  The 
upper  mandible  is  furnished  on  each  side  (in  the  specimen  examined 
by  me)  with  a  row  or  comb  formed  of  188  thin  elastic  laminae 
obliquely  bevelled  so  as  to  be  pointed,  and  placed  transversely  to 
the  long  axis  of  the  mouth.  They  arise  from  the  palate,  and  are 
attached  by  flexible  membrane  to  the  sides  of  the  mandible.  Those 
standing  towards  the  middle  are  the  largest,  being  about  one-third 
of  an  inch  in  length,  and  they  project  fourteen-hundredths  of  an 
inch  beneath  the  edge.  At  their  bases  there  is  a  short  subsidiary 
row  of  oblique  transverse  laminae.  In  these  several  respects  they 
resemble  the  plates  of  baleen  in  the  mouth  of  a  whale.  But  towards 
the  extremity  of  the  beak  they  differ  much,  as  they  project  inwards 
instead  of  straight  downwards.  The  entire  head  of  the  shoveller, 
though  incomparably  less  bulky,  is  about  one-eighteenth  of  the 
length  of  the  head  of  a  moderately  large  Balcenoptera  rostrata,  in 
which  species  the  baleen  is  only  nine  inches  long,   so  that  if  we 


DARWrN,   AND    THE   ORIGIN  OF  SPECIES  1 99 

were  to  make  the  head  of  the  shoveller  as  long  as  that  of  the 
Balasnoptera,  the  lamellae  would  be  six  inches  in  length ;  that 
is,  two-thirds  of  the  length  of  the  baleen  in  this  species  of  whale. 
The  lower  mandible  of  the  shoveller  duck  is  furnished  with  lamellae 
of  equal  length  with  those  above,  but  finer;  and  in  being  thus 
furnished  it  differs  conspicuously  from  the  lower  jaw  of  the  whale, 
which  is  destitute  of  baleen.  On  the  other  hand,  the  extremities 
of  the  lower  lamellae  are  frayed  into  fine  bristly  points,  so  that  they 
thus  curiously  resemble  the  plates  of  baleen.  In  the  genus  Prion,  a 
member  of  the  distinct  family  of  the  Petrels,  the  upper  mandible 
alone  is  furnished  with  lamellae,  which  are  well  developed  and 
project  beneath  the  margin,  so  that  the  beak  of  this  bird  in  this 
respect  resembles  the  mouth  of  a  whale. 

"  From  the  highly  developed  structure  of  the  shoveller's  beak 
we  may  proceed,  without  any  great  break,  as  far  as  fitness  for 
sifting  is  concerned,  through  the  beak  of  the  Merganetta  armata, 
and  in  some  respects  through  that  of  the  Aix  sponsa  to  the  beak 
of  the  common  duck.  In  this  latter  species  the  laminae  are  much 
coarser  than  in  the  shoveller,  and  are  firmly  attached  to  the  sides 
of  the  mandible  ;  they  are  only  about  fifty  in  number  on  each  side, 
and  do  not  project  at  all  beneath  the  margin.  They  are  square- 
tipped,  and  are  edged  with  translucent,  hardish  tissue,  as  if  for 
crushing  food.  The  edges  of  the  lower  mandible  are  crossed  by 
numerous  fine  ridges,  which  project  very  little.  Although  the  beak 
is  thus  very  inferior  to  that  of  the  shoveller  as  a  sifter,  yet  this  bird, 
as  every  one  knows,  constantly  uses  it  for  this  purpose.  There  are 
other  species  in  which  the  laminae  are  considerably  less  developed 
than  in  the  common  duck,  but  I  do  not  know  whether  they  use  their 
beaks  for  sifting  the  water. 

"  Turning  to  another  group  of  the  same  family.  In  the  Egyptian 
goose  (Chenoplax)  the  beak  closely  resembles  that  of  the  common 
duck;  but  the  laminae  are  not  so  numerous,  nor  do  they  project 
so  far  inwards;  yet  this  goose  uses  its  bill  like  a  duck  by  throwing 
the  water  out  of  the  corners.  Its  chief  food,  however,  is  grass, 
which  it  crops  like  a  common  goose.  In  the  latter  bird  the  laminae 
of  the  upper  mandible  are  much  coarser  than  in  the  common  duck, 
almost  confluent,  about  twenty-seven  in  number  on  each  side,  and 
terminating  upwards  in  tooth-like  knobs.     The  palate  is  also  covered 


200  THE  FOUNDATIONS   OF  ZOOLOGY 

with  hard,  round  knobs.  The  edges  of  the  lower  mandible  are 
serrated  with  teeth  much  more  prominent,  coarser,  and  sharper 
than'  in  the  duck.  The  common  goose  does  not  sift  the  water, 
but  uses  its  beak  exclusively  for  tearing  or  cutting  herbage, 
for  which  purpose  it  is  so  well  fitted  that  it  can  crop  grass 
closer  than  almost  any  other  animal.  There  are  other  species  of 
geese  in  which  the  laminae  are  less  developed  than  in  the  common 
goose. 

"  We  thus  see  that  in  a  member  of  the  duck  family  with  a  beak 
constructed  like  that  of  the  common  goose,  and  adapted  solely  for 
grazing,  or  even  a  member  with  a  beak  having  less  well  developed 
laminae,  might  be  converted  by  small  changes  into  a  species  like 
the  Egyptian  goose,  —  this  into  one  like  the  common  duck, — and, 
lastly,  into  one  like  the  shoveller,  provided  with  a  beak  almost 
exclusively  adapted  for  sifting  the  water ;  for  this  bird  could  hardly 
use  any  part  of  its  beak  except  the  hooked  tip  for  seizing  or  tearing 
solid  food. 

"  Returning  to  the  whales.  The  Hypcroddon  bideiis  is  desti- 
tute of  true  teeth  in  an  efificient  condition,  but  its  palate  is 
roughened  with  small,  unequal  points  of  horn.  There  is,  there- 
fore, nothing  improbable  in  supposing  that  some  early  Cetacean 
form  was  provided  with  similar  plates  of  horn  on  the  palate,  but 
rather  more  irregularly  placed,  and  which,  like  the  knobs  on  the 
beak  of  the  goose,  aided  it  in  seizing  or  tearing  its  food.  If  so, 
it  will  hardly  be  denied  that  the  points  might  have  been  con- 
verted through  variation  and  natural  selection  into  laminae  as  well 
developed  as  those  of  the  Egyptian  goose,  in  which  case  they 
would  have  served  exclusively  as  a  sifting  apparatus.  From  this 
stage,  in  which  the  laminae  would  have  been  two-thirds  of  the 
plates  of  baleen  of  the  Balcenoptera  rostrata,  gradations,  which 
may  still  be  observed  in  existing  Cetaceans,  lead  us  onwards  to 
the  enormous  plates  of  baleen  in  the  Greenland  whale.  Nor  is 
there  the  least  reason  to  doubt  that  each  step  in  this  scale  might 
have  been  as  serviceable  to  certain  ancient  Cetaceans,  with  the 
functions  of  the  parts  slowly  changing  during  the  progress  of 
development,  as  are  the  gradations  in  the  beaks  of  the  existing 
members  of  the  duck  family.  We  should  bear  in  mind  that  each 
species  of  duck  is    subjected    to    a    severe    struggle    for    existence, 


DARWIN;   AND    THE  ORIGIN  OF  SPECIES  20I 

and    that    the    structure    of    every    part    of     its    frame    must    be 
adapted  to  its  conditions  of  life."  ^ 

In  Romanes's  hands,  Mivart's  old  argument,  which  made  Dar- 
win more  strongly  convinced  of  the  correctness  of  his  own  views 
than  before,  assumes  a  new  form ;  for  he  attempts  to  show  that 
many  reflex  actions  have  been  brought  about  by  the  coadaptation 
of  parts  which  were  "  severally  useless,"  and  that  the  degree  of 
adaptation  exhibited  by  the  resulting  whole  is  often  so  slight  as 
to  be  incompatible  with  belief  that  the  reflex  response  has  now, 
or  ever  had,  "selective  value." 

While  he  holds  natural  selection  incompetent  to  account  for 
the  mechanism  which  brings  about  a  reflex  action  of  this  sort,  he 
believes  that  this  mechanism  may  be  satisfactorily  explained  as 
the  inherited  effect  of  use ;  for  he  says  that  the  doctrine  that 
constantly  associated  use  of  the  same  parts  for  the  performance 
of  the  same  action  will  progressively  organize  these  parts  into  a 
reflex  mechanism,  is  the  very  essence  of  the  theory  of  use-inheri- 
tance, —  no  matter  how  high  a  degree  of  coadaptation  may  thus 
be  reached  on  the  one  hand,  or  how  low  a  degree  of  utilitarian 
value  on  the  other. 

"  In  our  organization,"  he  says  in  illustration,  "  there  is  a 
reflex  mechanism  which  insures  the  prompt  withdrawal  of  the  legs 
from  any  source  of  irritation  supplied  to  the  feet.  For  instance, 
after  a  man  has  broken  his  spine  in  such  a  manner  as  totally  to 
interrupt  the  functional  continuity  of  his  spinal  cord  and  brain,, 
the  reflex  mechanism  in  question  will  continue  to  retract  his 
legs  when  his  feet  are  stimulated  by  a  touch,  a  burn,  etc.  This 
action  is  clearly  a  responsive  action,  and,  as  the  man  neither  feels 
the  stimulus  nor  the  resulting  movement,  it  is  as  clearly  a 
reflex  action.  The  question  now  is  as  to  its  mode  of  origin  and 
development. 

"  I  ask  whether  we  can  reasonably  hold  that  this  particular 
reflex  action  —  comparatively  simple  though  it  be  —  has  ever 
been  of  selective  value  to  the  human  species,  or  to  the  ancestors 
thereof  ?  Even  in  its  present  fully  formed  condition  it  is  fairly 
questionable  whether  it  is  of  any  adaptive  value  at  all.  The 
movement    performed   is   no    doubt     an    adaptive    movement;    but 

1  "Origin,"  pp.  182-186. 


202  THE  FOUNDATIONS   OF  ZOOLOGY 

is  there  any  occasion  upon  which  the  reflex  mechanism  concerned 
therein  can  ever  have  been  of  adaptive  usef  Until  a  man's  legs 
have  been  paralyzed  as  to  their  voluntary  motion,  he  will  always 
promptly  withdraw  his  feet  from  any  injurious  source  of  irritation 
by  means  of  his  conscious  intelHgence.  True,  the  reflex  mechan- 
ism secures  an  almost  inappreciable  saving  in  the  time  of  response 
to  a  stimulus  as  compared  with  the  time  required  for  response  to 
an  act  of  will ;  but  the  difference  is  so  exceedingly  small,  that  we 
can  hardly  suppose  the  saving  of  it  in  this  particular  case  can  be 
a  matter  of  any  adaptive  —  much  less  selective  —  importance. 

"  Nor  is  it  more  easy  to  suppose  that  the  reflex  mechanism 
has  been  developed  by  natural  selection  for  the  purpose  of  replac- 
ing voluntary  action  when  the  latter  has  been  destroyed  or  sus- 
pended by  grave  spinal  injury,  paralysis,  coma,  or  even  ordinary 
sleep.  In  short,  even  if  for  the  sake  of  argument  we  allow  it  to 
be  conceivable  that  any  human  being,  ape,  or  still  more  distant 
ancestor,  has  ever  owed  its  life  to  the  possession  of  this  mechan- 
ism, we  may  still  be  certain  that  not  one  in  a  million  can  have 
done  so.  And  if  this  is  the  case  with  regard  to  the  mechanism 
as  fully  constructed,  still  more  must  it  have  been  the  case  with 
regard  to  all  the  previous  stages  of  construction.  For  here,  with- 
out elaborating  the  point,  it  would  appear  that  a  process  of  con- 
struction by  survival  of  the  fittest  is  incomprehensible."  ^ 

As  Romanes  says  that  this  is  a  typical  illustration  of  the  diffi- 
culty he  finds  in  explaining  the  production  of  reflex  actions  in 
general  by  selection  alone,  it  may  be  worth  while  to  examine  it ; 
although  the  source  of  Romanes's  difficulty  is  hard  to  discover. 

When  all  the  complicated  muscles  of  the  foot  and  leg  and 
trunk  are  at  rest,  the  irritation  of  the  sole  may  be  followed  by  vio- 
lent retraction  of  the  foot,  but  when  they  are  brought  into  bal- 
anced action  in  the  complex  movements  of  walking  or  running, 
this  does  no  more  than  to  counterbalance  and  thus  arrest  some 
of  these  movements.  The  importance  of  perfect  locomotor  coor- 
dination is  so  clear  to  all  that  a  moment's  thought  must  show 
that  the  past  history  of  our  race  has  furnished  abundant  oppor- 
tunities for  the  perfection  of  this  coordination  by  selection.  No 
one  who   reflects   how   often  the  life  of   a   barefooted    savage    and 

1  "  Darwin  and  after  Darwin,"  II.,  pp.  73-77. 


DARWIN,   AND    THE  ORIGIN  OF  SPECIES  203 

the  lives  of  all  who  depend  upon  him  for  food  must  be  staked 
upon  his  ability  to  creep  silently  and  rapidly  to  the  side  of  his 
unsuspecting  enemy,  or  upon  his  power  to  elude  his  pursuers  by 
stealth,  or  upon  his  skill  in  stalking  his  prey  without  warning  it 
by  any  movements  which  may  be  detected  by  it';  delicate  and 
alert  senses,  —  no  one  who  bears  all  this  in  mind  can  doubt  that 
the  ability  to  arrest  the  descending  foot  before  it  treads  upon  a 
thorn  or  cracks  a  dry  twig,  has  selective  value.  But,  says  Ro- 
manes, even  if  we  admit  that  the  sole  of  the  foot  has  selective 
value,  the  savage  is  able  to  interpret  its  warnings  and  to  adjust 
his  footsteps  intelligently;  and  while  the  reflex  mechanism  acts 
a  little  more  promptly,  the  saving  of  time  is  too  small  to  have 
selective  value.  I  am  not  aware  that  any  one  has  measured  the 
time  required  to  drive  into  the  foot  a  thorn  which  has  scratched 
it,  or  the  time  required  for  cracking  a  dry  twig  which  the  foot 
has  touched ;  but  Romanes  tells  us  in  an  other  place  ("  Mind  and 
Motion  and  Monism,"  p.  9)  that  while  a  nerve-centre  requires 
only  about  one-twentieth  of  a  second  to  perform  its  part  in  a 
reflex  action,  where  no  thought  or  consciousness  is  involved,  the 
operations  which  are  comprised  in  perceiving  a  simple  sensation, 
and  the  volitional  act  of  signalling  the  perception,  cannot  be  per- 
formed in  less  than  one-twelfth  of  a  second,  which  is  nearly  twice 
as  long  as  the  time  required  by  the  lower  nerve-centres  for  the 
performance  of  the  reflex  action. 

It  seems  probable  that,  in  less  than  a  thirtieth  of  a  second,  a 
scratch  from  a  thorn  might  have  become  a  disabling  injury, 
which  would  place  a  warrior  at  the  mercy  of  his  pursuer;  or  that 
the  prey  which  might  have  preserved  the  hunter  and  his  family 
from  starvation  might  be  alarmed  by  the  crackling  of  a  twig  in 
as  short  a  time ;  although  the  mere  saving  of  time  is,  no  doubt, 
less  valuable  than  the  freedom  from  care  about  his  footsteps 
which  permits  the  warrior  or  the  huntsman  to  fix  every  sense 
and  every  faculty  on  the  matter  in  hand,  and  to  trust  to  this 
reflex  mechanism  for  prompt  warning  by  the  mechanical  arrest 
of  a  dangerous  step  long  enough  for  conscious  intelligence  to 
seek  a  place  to  finish  it. 

But  Romanes  says  he  does  not  see  how  we  are  to  explain 
either   the    origin    or   the  development  of    a   reflex   mechanism    by 


204  THE  FOUNDATIONS   OF  ZOOLOGY 

selection  alone;  for  even  if  we  admit  all  that  has  been  said,  it 
seems  to  him  to  be  self-evident  that  a  reflex  action  must,  from  its 
very  nature,  already  be  given  in  a  state  of  working  efficiency  if  it 
is  to  work  at  all  so  as  to  count  for  anything  in  the  struggle 
for  life. 

The  history  of  the  adjustment  between  tactile  and  muscular 
sensations  and  the  orderly  balancing  of  all  the  movements  con- 
cerned in  locomotion  has  been  so  long  and  complicated  that  we 
know  little  of  its  details,  but  I  am  not  sure  I  understand  what 
Romanes  means  by  working  efficiency.  While  slight  irritation 
of  the  sole  is  followed  by  retraction  of  the  foot,  more  prolonged 
irritation  is  followed,  especially  in  the  young,  who  have  not  yet 
learned  to  repress  them,  by  indefinite  but  violent  involuntary 
movements  in  many  parts  of  the  body,  and  I  fail  to  see  why  any 
of  these  vague  movements  might  not  have  been  picked  out  by 
natural  selection,  if  peculiarly  useful,  and  gradually  made  more 
delicate  and  more  definite  and  more  useful ;  nor  can  I  see  why 
each  step  in  this  process  of  gradual  specialization  may  not  have 
been  beneficial,  or  why  it  may  not  have  had  selective  value. 

All  admit  that  while  natural  selection  picks  out,  and  preserves, 
it  produces  nothing,  and  if  we  can  show  how  it  corrects  our  bodily 
movements  and  reduces  them  to  exactness  by  giving  us  distinct 
actions  instead  of  confused  and  perplexed  ones,  I  fail  to  see  why 
this  process  should  not  be  gradual.  Romanes,  it  is  true,  seems 
to  believe  that  responses  which  are  now  brought  about  involun- 
tarily or  unconsciously,  by  adaptive  structure,  would  be  easier  to 
understand  if  we  could  show  that  they  arose  as  "  consciously  intel- 
ligent adjustments";  for  he  holds  that  the  inheritance  of  the 
effects  of  use  furnishes  an  explanation  of  the  origin  of  the  adap- 
tations which  natural  selection  picks  out  and  preserves,  inasmuch 
as  it  shows  how  natural  selection  has  been  aided  by  "consciously 
intelligent  action " ;  but  I  cannot  reconcile  with  other  opinions 
which  I  find  in  Romanes's  works,  his  belief  that  a  reflex  response 
would  be  any  easier  to  understand  if  we  could  show  that  it  was, 
at  one  time,  rational  and  accompanied  by  consciousness  and 
volition. 

Many  thinkers  of  no  little  eminence,  Romanes  among  them, 
hold  the   opinion    that    not  only  instincts   and    habits,  but   rational 


DARWm,  AND   THE  ORIGIN  OF  SPECIES  20$ 

actions  as  well,  may  some  time  prove  to  be  reflex  from  the  begin- 
ning to  the  end  of  their  history.  There  are  men  of  science  who 
believe  that  it  may  some  time  be  proved  that  when  we  perform  an 
action  because  our  reason  approves  it,  neither  the  response  nor  the 
approval  of  our  reason  is  anything  more  than  exhaustive  know- 
ledge of  our  organic  mechanism  would  lead  one  to  expect.  No 
one  who  admits  that,  for  all  he  knows  to  the  contrary,  rational 
actions  may  be  reflex  in  this  sense,  can,  in  consistency,  believe 
that  the  origin  of  an  adaptive  mechanism  which  is  used  intelli- 
gently is  any  easier  to  understand  than  the  origin  of  one  which  is 
used  unconsciously. 

Romanes  is  not  content  with  the  admission  that,  for  all  one 
knows,  rational  actions  may  thus  be  mechanical ;  for  he  accepts 
this  as  a  thing  proved  and  accomplished,  and  says,  "  I  think  we 
may  fairly  expect  that  within  a  time  less  remote  than  the  two  cen- 
turies which  separate  us  from  Hobbes,  the  course  of  ideas  in  a  given 
train  of  thought  will  admit  of  having  its  footsteps  tracked  in  the 
corresponding  pathways  of  the  brain.  Be  this,  however,  as  it 
may,  even  now  we  know  enough  to  say  that,  whether  or  not  these 
footsteps  will  ever  admit  of  being  thus  tracked  in  detail,  they  are 
all  certainly  present  in  the  cerebral  structure  of  each  one  of  us. 
What  we  know  on  the  side  of  mind  as  logical  sequence  is,  on  the 
side  of  the  nervous  system,  nothing  more  than  the  passage  of 
nervous  energy  through  one  series  of  cells  and  fibres  rather  than 
another ;  what  we  recognize  as  truth  is  merely  the  fact  of  the 
brain  vibrating  in  tune  with  nature."  ^ 

While  thus  convinced  that  rational  actions  are  mechanical, 
Romanes  holds  that  proof  that  instincts  which  are  now  mechan- 
ical arose  as  "  consciously  intelligent  adjustments "  would  make 
the  history  of  these  adjustments  easier  to  understand. 

"  If  function  produces  structure  in  the  race,  as  it  does  in  the 
individual,"  he  says  ("  Darwin  and  after  Darwin,"  I.,  p.  %6\  "the  vol- 
untary and  frequently  repeated  actions  may  very  well  have  led  ta 
an  organic  integration  of  the  neuro-muscular  mechanism  concerned. 

"  Thus  with  regard  to  the  phenomena  of  reflex  action  in  gen- 
eral, all  the  facts  are  such  as  this  theory  (the  inheritance  of  the 
effects  of    use)  requires,  while  many  of  the  facts  are  such  as  the 

1  "  Mind  and  Motion,  and  Monism,"  p.   17. 


206  THE  FOUNDATIONS  OF  ZOOLOGY 

theory  of  natural  selection  alone  cannot  conceivably  explain.  In- 
deed, it  is  not  too  much,"  says  he,  "to  say  that  most  of  the  facts 
are  such  as  directly  to  contradict  the  latter  theory  in  its  application 
to  them.  I  have  endeavored,"  he  says,  "  to  show  that  we  have  a 
large  class  of  such  cases  in  the  domain  of  reflex  action,  and  shall 
next  endeavor  to  show  that  there  is  another  large  class  in  the 
domain  of  instinct.  .  .  . 

"  If  instinct  be  hereditary  habit,  i.e.  if  it  comprises  an  element 
of  transmitted  experience,  we  at  once,"  says  Romanes,  "  find  a 
complete  explanation  of  many  cases  of  the  display  of  instinct  which 
otherwise  remain  inexplicable.  In  all  cases  where  instincts  become 
complex  and  refined,  we  seem  almost  compelled  to  accept  the  view 
that  their  origin  is  to  be  sought  in  consciously  intelligent  adjust- 
ments on  the  part  of  ancestors. 

"  Thus,  to  give  only  one  example,  a  species  of  Sphex  preys  upon 
caterpillars  which  it  stings  in  their  nerve-centres  for  the  purpose 
of  paralyzing,  without  killing  them.  The  victims,  when  thus  ren- 
dered motionless,  are  then  buried  with  the  eggs  of  the  Sphex,  in 
order  to  serve  as  food  for  her  larvae  which  subsequently  develop 
from  these  eggs.  Now,  in  order  to  paralyze  a  caterpillar,  the 
Sphex  has  to  sting  it  successively  in  nine  minute  and  particular 
points  along  the  ventral  surface  of  the  animal  —  and  this  the  Sphex 
unerringly  does,  to  the  exclusion  of  all  other  points  of  the  cater- 
pillar's anatomy.  Well,"  says  Romanes,  "such  being  the  fact, 
it  is  conceivable  enough  that  the  ancestors  of  the  Sphex,  being, 
like  many  other  hymenopterous  insects,  highly  intelligent,  should 
have  observed  that  on  stinging  caterpillars  in  these  particular  spots 
a  greater  amount  of  effect  was  produced  than  could  be  produced 
by  stinging  them  anywhere  else ;  and  therefore  that  they  habit- 
ually stung  the  caterpillars  in  these  places  only,  till,  in  course  of 
time,  this  originally  intelligent  habit  became  by  heredity  instinc- 
tive. But  now,  on  the  other  hand,  if  we  exclude  the  possibility 
of  this  explanation,  it  appears  to  me  incredible  that  such  an 
instinct  should  ever  have  been  evolved  at  all ;  for  it  appears  to 
me  incredible  that  natural  selection  unaided  by  originally  intelligent 
action  could  ever  have  developed  such  an  instinct  out  of  merely 
fortuitous  variations  —  there  being,  by  the  hypothesis,  nothing  to 
determine  variations  of  an  insect's  mind  in  the  direction  of  stinging 


DARWIN,   AND    THE  ORIGIN  OF  SPECIES  20/ 

caterpillars  in  only  these  nine  intensely  localized  spots.  Finally, 
in  the  case  of  our  species,  it  is  self-evident,"  says  Romanes,  "  that 
the  aesthetic,  moral,  and  religious  instincts  admit  of  a  natural  and 
easy  explanation  on  the  hypothesis  of  use-inheritance,  while  such 
is  by  no  means  the  case  if  that  hypothesis  be  rejected." 

No  phenomena  in  the  whole  realm  of  nature  are  more  difficult 
to  handle  than  those  Romanes  here  refers  to.  Many,  no  doubt, 
think,  with  him,  that  they  are  inexplicable  by  natural  selection, 
although  few  among  those  who,  so  far,  think  as  he  does,  seem 
likely  to  find  satisfaction  in  that  view  of  morality  and  religion 
which  attributes  these  things  to  the  inheritance  of  the  effects  of 
use. 

We  have  already  asked,  page  66,  what  evidence  there  is  that 
function  ever  does  produce  structure,  either  in  the  race  or  in  the 
individual ;  and  we  have  seen  that  when  organs  are  improved  by 
normal  use,  structures  for  bringing  this  useful  end  about  already 
exist.  Capacity  for  improvement  by  practice  is  itself  an  adapta- 
tion which  calls  for  explanation,  rather  than  an  explanation  or 
cause  of  adaptation. 

The  opinion  that  deliberate  acts,  habits,  instincts,  and  reflex 
acts  form  a  descending  series,  in  which  each  lower  manifestation 
has,  at  some  time  in  the  past,  climbed  down  from  the  top  of  the 
ladder  seems  to  commend  itself  to  many.  For  this  reason  I  have 
quoted  Romanes's  recent  statement  at  some  length,  although  no 
one  can,  with  logical  consistency,  find,  in  this  opinion,  even  if  it 
be  well  founded,  any  help  in  accounting  for  the  origin  of 
instincts,  or  that  of  reflex  acts,  if  deliberate  acts  are  themselves 
mechanical  and  dependent  upon  the  presence  of  adaptive  structure. 

If  practice  does  no  more  than  to  correct  responsive  actions 
and  to  reduce  them  to  exactness  by  the  repression  of  those  that 
are  vague  and  indefinite  and  by  the  preservation  of  those  that 
are  exact  and  definite,  how  can  it  add  anything  to  the  nature  of 
organisms  .-•  Romanes  not  only  considers  it  proved  that  delib- 
erate acts  are  mechanical,  but  he  also  holds  that  the  only  way 
to  escape  what  he  regards  as  the  materialistic  consequences  of 
this  conviction  is  to  be  found  in  the  monistic  creed  that  "  the 
antithesis  between  mind  and  motion  —  subject  and  object  —  is 
itself  phenomenal  or  apparent ;   not  absolute  or  real."     "  We  have 


208  THE  FOUNDATIONS  OF  ZOOLOGY 

only  to  suppose,"  he  says,  "  that  the  seeming  duality  is  relative 
to  our  modes  of  apprehension ;  and,  therefore,  that  any  change 
taking  place  in  the  mind,  and  any  change  taking  place  in  the 
brain,  are  not  two  changes,  but  one  change."  "  To  suppose  mind 
the  cause  of  motion,  or  motion  the  cause  of  mind,  is  equally  to 
suppose  that  which  is  neither  true  nor  untrue,  but  nonsensical." 
"  It  is  equally  nonsense  to  speak  of  mental  action  causing  cerebral 
action,  or  of  cerebral  action  causing  mental  action,  nonsense  of 
the  same  kind  as  it  would  be  to  speak  of  the  '  Pickwick  Papers ' 
causing  a  storm  at  sea,  or  the  eruption  of  a  volcano  causing  the 
forty-seventh  proposition  of  the  first  book  of  Euclid." 

I  am  myself  quite  unable  to  see  how  one  who  holds  it 
nonsense  to  suppose  mind  can  cause  motion,  can  for  a  moment 
think  the  origin  of  a  reflex  act  or  automatic  response  would  be 
easier  to  understand  through  proof  that  it  was,  at  one  time, 
accompanied  by  conscious  intelligence.  Neither  they  who  know 
no  reason  why  thought  should  not,  some  day,  be  reduced  to 
mechanics,  nor  they  who  believe,  with  Romanes,  that  this  has 
already  been  accomplished,  can,  in  consistency,  believe  that  use 
directed  by  intelligence  can  either  bring  about  adaptive  structures, 
or  supply  to  natural  selection  even  the  incipient  stages  of  adaptive 
modification,  unless  they  attribute  this  adaptive  influence  to  mere 
use,  in  itself,  and  not  to  the  guidance  of  use  by  intelligence.  If 
the  Lamarckians  tell  us  that  this  is  their  contention,  and  that  it 
is  mere  use  in  itself  that  brings  about  adaptive  structures,  is  it 
not  obvious  that,  inasmuch  as  rational  actions  are,  as  a  rule,  more 
complicated  than  those  we  call  reflex,  their  origin  is  not  easier, 
but  harder,  to  understand  .-• 

If  we  agree  with  Romanes  that  "what  we  know  on  the  side 
of  mind  as  logical  sequence  is  on  the  side  of  the  nervous  system, 
nothing  more  than  the  passage  of  nervous  energy  through  one 
series  of  cells  and  fibres  rather  than  another,"  how  can  practice 
in  logical  reasoning  bring  about  any  of  these  cells  or  fibres  or 
direct  nervous  energy  into  one  series  rather  than  another,  except 
so  far  as  adaptive  mechanism  for  bringing  this  about  already 
exists } 

If  "what  we  know  as  truth  is  merely  the  fact  of  the  brain 
vibrating   in   tune  with    nature,"  is   the   belief   that   natural    know- 


DARWIN,  AND   THE  ORIGIN  OF  SPECIES  209 

ledge  adds  anything  to  our  nature  more  or  less  than  belief  that 
the  brain  is  made  to  vibrate  in  tune  with  nature  by  vibrating  in 
tune  with  nature  ?  Is  this  belief  any  more  significant  or  any  more 
instructive  than  belief  that  the  brain  is  made  to  vibrate  in  tune 
with  nature  by  the  "  Pickwick  Papers  "  ? 

It  may  be  well  to  dwell  a  little  on  the  assertion  that  what  we 
know  as  truth  is  merely  the  vibration  of  a  brain  in  tune  with 
nature ;  and  to  ask  what  these  words  mean.  Vibrations  are  said 
to  be  demonstrated  when,  directly  or  indirectly,  we  are  made  to 
perceive  them  by  our  senses ;  nor  do  I  suppose  that  Romanes 
could  ask  or  hope  for  better  proof  of  his  assertion  than  the 
demonstration,  to  our  senses,  of  the  actual  vibration  of  a  brain 
in  tune  with  nature  whenever  a  truth  arises  in  the  mind. 
Whether  we  share  his  confidence  that  this  proof  will  be  found 
in  the  next  two  hundred  years  or  not,  we  may  ask  what  it  would 
mean,  if  found. 

It  is  a  truth  that  stones  are  heavy,  and  the  vibration  of  a 
brain  in  tune  with  heaviness  under  the  visual  stimulus  of  a  stone 
would  be  a  response ;  but  we  know  no  reason  why  extended 
bodies  should  have  weight,  except  that  the  fact  is  so.  With- 
out, at  present,  asking  Berkeley's  old  question  whether  sensible 
vibrations  of  the  brain  or  of  anything  else  can  exist  otherwise 
than  in  a  mind,  may  we  not  ask  whether  the  vibration  of  the 
brain  in  tune  with  heaviness  would  tell  us  why  we  should  think 
the  thought  that  stones  are  heavy,  any  more  than  the  fact  that 
stones  are  heavy  tells  us  why  they  should  be  .''  Would  the  sen- 
sible perception  of  the  vibrations  of  our  brains  in  tune  with 
nature,  whenever  a  truth  arises  in  our  minds,  tell  us  anything 
except  that,  with  experience,  comes  knowledge .''  Would  it  be  any 
reason  why  this  should  be  the  case  except  that  the  fact  is  so  .'' 
And  do  we  not  now  all  admit  this  as  a  fact .-' 

We  have  good  reason  to  hope  that  practical  advantage  to 
mankind  will  follow  progress  in  the  physiology  of  the  brain,  as 
it  has  followed  all  progress  in  natural  knowledge ;  although  it  is 
hard  to  see  what  use  there  could  be  in  proof  that  truth  is  the 
vibration  of  a  brain  in  tune  with  nature,  unless  we  also  discover, 
outside  our  brains,  some  way  to  tell  when  their  vibrations  are  in 
tune. 


2IO  THE  FOUNDATIONS  OF  ZOOLOGY 

I  cannot  conceive  what  better  basis  for  a  philosophy  of  mind 
and  matter  one  who  had  seen  the  vibrations  of  a  brain  would 
have  than  one  who  knows  he  sees,  and,  as  a  rule,  sees  to  his 
advantage,  when  he  opens  his  eyes. 

Must  we  not  also  reflect  that  some  of  the  things  we  see  may 
be  hallucinations,  or  illusions,  or  somnambulatory  dreams  ?  Must 
we  not  ask  the  difficult  but  preeminently  practical  question  how, 
admitting  the  vibrations,  we  distinguish  those  that  are  in  tune 
with  nature  from  those  that  are  out  of  tune  ?  How,  for  example, 
do  the  vibrations  that  go  on  as  we  think  the  thought  that  a  stick 
half  in  water  is  bent,  differ  from  those  that  go  on  as  we  think 
that  the  stick  in  the  air  is  straight  ?  Is  it  not  because  "  snap  " 
judgments  about  our  sensible  perceptions  often  lead  us  into  diffi- 
culties and  tend  to  our  physical  destruction ;  while  rectified  judg- 
ments are  beneficial ;  because,  for  example,  the  savage  who  has 
corrected  his  judgment  spears  his  fish,  while  he  who  has  not 
loses  his  dinner.  May  not  the  difference  perhaps  prove,  in  ulti- 
mate analysis,  to  be  that  adjustments  that  are  preservative  of  life 
are  said  to  be  in  tune  with  nature,  and  their  corresponding  mental 
states  truths;  while  those  that  are  injurious  are  said  to  be  out  of 
tune,  and  their  corresponding  mental  states  errors  or  illusions } 
May  it  not  be  because  our  brains  are  the  ones  that  have  so  far 
survived  the  struggle  for  existence  that  we  hold  their  normal 
vibrations  to  be  in  tune  with  nature  }  If  this  should  prove  to  be 
the  case,  would  it  not  be  due  to  natural  selection  that  our  brains 
vibrate  in  tune  with  nature }  If  it  were  not  for  natural  selection, 
might  not  all  seem  delusion ;    nothing  truth  ? 

No  Darwinian  questions  the  benefit  of  training,  and  practice, 
and  education,  and  experience ;  for  all  this  is  matter  of  fact, 
admitted  by  all.  Who  can  ask  whether  a  man  educated  is  differ- 
ent from  the  man  uneducated  ?  or  whether  the  beneficial  effects 
of  nurture  are  anything  more  than  might  have  been  expected  } 

While  he  admits  that,  in  some  practical  sense  of  the  words,  he 
is  a  free  agent,  responsible  for  his  thoughts  and  actions,  and 
able  to  act  wisely  or  foolishly  and  to  do  right  and  wrong ;  the 
Darwinian  asks  whether  voluntary  acts  are  efficient  causes  of 
structure,  or  only  antecedents  of  the  sort  which  we  call  physical 
causes,   or   occasions,  or    stimuli;    and   whether   they  do    anything 


DARWIN;  and   the  origin  of  species  21  r 

more  than  to  make  manifest  what  was  latent  or  potential.  When 
pressed  for  a  definition  of  latent  potency,  can  he  do  more  than  to 
assert  that  activity  is  latent  in  a  body  if,  while  this  body  does  what 
he  expects  under  certain  conditions,  knowledge  of  these  conditions 
does  not  tell  him  why  it  should  ?  He  asks,  furthermore,  whether 
it  is  conceivable  that  one  cubit  can  be  added  to  his  stature  by 
taking  thought,  either  for  one  lifetime  or  for  a  million ;  although 
he  admits  that  no  one  could  expect  to  attain  to  his  normal  or 
natural  stature  without  the  stimulus  of  healthy  muscular  and 
nervous  activity.  He  also  asks  whether  the  improvement  of  our 
faculties  by  use  is  anything  more  than  the  correction  of  our 
natural  responses,  and  their  reduction  to  exactness,  by  the  suppres- 
sion of  those  that  are  confused  and  perplexed,  and  the  survival 
of  those  that  are  definite  and  distinct ;  and,  ultimately,  by  the 
extinction  of  the  deluded  minds  and  the  survival  of  those  that 
are  sane ;  and  whether  the  history  of  individual  life  is  anything 
more  than  the  continuance  of  the  process  of  natural  selection. 

Some  hold  that  our  race  has,  by  its  intelligence,  emancipated 
itself  from  natural  selection,  and  escaped  from  its  domain  into  the 
realm  of  reason ;  but  if  we  agree  with  Berkeley  that  the  work 
of  experience  "  is  to  unravel  our  prejudices  and  mistakes,  grad- 
ually correcting  our  judgment  and  reducing  it  to  a  philosophical 
exactness,"  may  we  not  ask  whether  knowledge  itself  is  anything 
more  than  conscious  apprehension  of  the  unceasing  activity  of 
the  selective  process .-' 

Darwin  points  out,  even  in  the  first  edition  of  the  "  Origin,'* 
many  difficulties  which  he  is  not  able  to  solve.  Some  of  them 
have  been  ably  treated  by  later  writers.  Some  are  still  unex- 
plained, and  in  the  next  lecture  I  shall  try  to  throw  new  light 
upon  one  of  them. 


LECTURE    IX 

NATURAL   SELECTION,   AND   THE   ANTIQUITY   OF 

LIFE 


LECTURE    IX 

NATURAL   SELECTION,  AND  THE  ANTIQUITY  OF  LIFE 

In  the  "Origin  of  Species"  Darwin  says  that  the  sudden  appear- 
ance of  species  belonging  to  several  of  the  main  divisions  of  the 
animal  kingdom  in  the  lowest  known  fossiliferous  rocks  is  at  pres- 
ent inexplicable,  and  may  be  truly  urged  as  a  valid  objection  to 
his  views. 

If  his  theory  be  true,  he  says  that  "  it  is  indisputable  that 
before  the  lowest  Cambrian  stratum  was  deposited  long  periods 
elapsed,  as  long  as,  or  probably  far  longer  than,  the  whole  interval 
from  the  Cambrian  age  to  the  present  day,  and  that  during  these 
vast  periods  the  world  swarmed  with  living  creatures.  Here," 
he  says,  "we  encounter  a  formidable  objection;  for  it  seems 
doubtful  whether  the  earth,  in  a  fit  state  for  the  habitation  of 
living  creatures,  has  lasted  long  enough.  To  the  question  why 
we  do  not  find  such  fossiliferous  deposits  belonging  to  these 
assumed  earliest  periods  prior  to  the  Cambrian  system  I  can  give 
no  satisfactory  answer." 

On  its  geological  side  this  difficulty  is  even  greater  than  it  was 
in  Darwin's  day,  for  we  now  know  that  the  fauna  of  the  Lower 
Cambrian  was  rich  and  varied  ;  that  most  of  the  modern  types  of 
animal  life  were  represented  in  the  oldest  fauna  which  has  been 
discovered,  and  that  all  its  types  have  modern  representatives. 
The  paleontological  side  of  the  subject  has  been  ably  summed  up 
by  Walcott  in  an  interesting  memoir  on  the  oldest  fauna  which 
is  known  to  us  from  fossils,  and  his  collection  of  one  hundred 
and  forty-one  American  species  from  the  Lower  Cambrian  is  dis- 
tributed over  most  of  the  marine  groups  of  the  animal  kingdom, 
and,  except  for  the  absence  of  the  remains  of  vertebrated  animals, 
the  whole  province  of  animal  life  is  almost  as  completely  covered 

215 


2l6  THE  FOUNDATIONS  OF  ZOOLOGY 

by  these  one  hundred  and  forty-one  species  as  it  could  be  by  a 
collection  from  the  bottom  of  the  modern  ocean.  Four  of  the 
American  species  are  sponges,  two  are  hydrozoa,  nine  are  actino- 
zoa,  twenty-nine  are  brachiopods,  three  are  lamellibranchs,  thir- 
teen are  gasteropods,  fifteen  are  pteropods,  eight  are  Crustacea, 
fifty-one  are  trilobites,  and  trails  and  burrows  show  the  existence 
of  at  least  six  species  of  bottom  forms,  probably  worms  or  Crusta- 
cea. The  most  notable  characteristic  of  this  fauna  is  the  com- 
pleteness with  which  these  few  species  outline  the  whole  fauna 
of  the  modern  sea-floor.  Far  from  showing  us  the  simple  unspe- 
cialized  ancestors  of  modern  animals,  they  are  most  intensely  modern 
themselves  in  the  zoological  sense,  and  they  belong  to  the  same 
order  of  nature  as  that  which  prevails  at  the  present  day. 

The  fossiliferous  beds  of  the  Lower  Cambrian  rest  upon  beds 
which  are  miles  in  vertical  thickness,  and  are  identical  in  all  their 
physical  features  with  those  which  contain  this  fauna.  They 
prove  beyond  question  that  the  waters  in  which  they  were  laid 
down  were  as  fit  for  supporting  life  at  the  beginning  as  at  the 
end  of  the  enormous  lapse  of  time  which  they  represent,  and 
that  all  the  conditions  have  since  been  equally  favorable  for  the 
preservation  and  the  discovery  of  fossils.  Modern  discovery  has 
brought  the  difficulty  which  Darwin  points  out  into  clearer  view, 
but  geologists  are  no  more  prepared  than  he  was  to  give  a  satis- 
factory solution,  although  I  shall  now  try  to  show  that  the  study 
of  living  animals  in  their  relations  to  the  world  around  them  does 
help  us,  and  that  comparative  anatomy  and  comparative  embry- 
ology and  the  study  of  the  habits  and  affinities  of  organisms  tel^ 
us  of  times  more  ancient  than  the  oldest  fossils,  and  give  a  more 
perfect  record  of  the  early  history  of  life  than  paleontology. 

While  the  history  of  life  as  told  by  fossils  has  been  slow  and 
gradual,  it  has  not  been  uniform,  for  we  have  evidence  of  the 
occurrence  of  several  periods  when  modification  was  comparatively 
rapid. 

We  are  living  in  a  period  of  intellectual  progress,  and  among 
terrestrial  animals  cunning  now  counts  for  more  than  size  or 
strength,  and  fossils  show  that,  while  the  average  size  of  mam- 
mals has  diminished  since  the  Middle  Tertiary,  the  size  of  their 
brains  has  increased  more    than  one    hundred    per    cent ;    that  the 


NATURAL   selection;   AND    THE  ANTIQUITY  OF  LIFE     21/ 

brain  of  a  modern  mammal  is  more  than  twice  as  large,  compared 
with  its  body,  as  the  brain  of  its  ancestors  in  the  Middle  Tertiary. 
Measured  in  years  the  Middle  Tertiary  is  very  remote,  but  it  is 
very  modern  compared  with  the  whole  history  of  the  fossiliferous 
rocks,  although  more  of  brain  development  has  been  effected  in 
this  short  time  than  in  all  preceding  time  from  the  beginning. 

The  later  paleozoic  and  early  secondary  fossils  mark  another 
period  of  rapid  change,  when  the  fitness  of  the  land  for  animal 
life,  and  the  presence  of  land  plants,  brought  about  the  evolution 
of  terrestrial  animals. 

I  shall  give  reasons  for  seeing,  in  the  Lower  Cambrian,  another 
period  of  rapid  change,  when  a  new  factor  —  the  discovery  of 
the  bottom  of  the  ocean  —  began  to  act  in  the  modification  of 
species,  and  I  shall  try  to  show  that,  while  animal  life  was  abun- 
dant long  before,  the  evolution  of  animals  likely  to  be  preserved 
as  fossils  took  place  with  comparative  rapidity,  and  that  the  zoologi- 
cal features  of  the  Lower  Cambrian  are  of  such  a  character  as 
to  indicate  that  it  is  a  decided  and  unmistakable  approximation 
to  the  primitive  fauna  of  the  bottom,  beyond  which  life  was  repre- 
sented only  by  minute  and  simple  surface  animals  not  likely  to 
be  preserved  as  fossils. 

Nothing  brings  home  more  vividly  to  the  zoologist  a  picture 
of  the  diversity  of  the  Lower  Cambrian  fauna  and  of  its  intimate 
relation  to  the  fauna  on  the  bottom  of  the  modern  ocean  than  the 
thought  that  he  would  have  found  on  the  old  Cambrian  shore  the 
same  opportunity  to  study  the  embryology  and  anatomy  of  ptero- 
pods  and  gasteropods  and  lamellibranchs,  of  Crustacea  and  medusae, 
echinoderms  and  brachiopods,  that  he  now  has  at  a  marine  labora- 
tory ;  that  his  studies  would  have  followed  the  same  Hnes  then 
that  they  do  now,  and  that  most  of  the  record  of  the  past  which 
they  make  known  to  him  would  have  been  ancient  history  then. 
Most  of  the  great  types  of  animal  life  show  by  their  embryology 
that  they  run  back  to  simple  and  minute  ancestors  which  lived  at 
the  surface  of  the  ocean,  and  that  the  common  meeting  point  must 
be  projected  back  to  a  still  more  remote  time,  before  these  ancestors 
had  become  differentiated  from  each  other. 

After  we  have  traced  each  great  line  of  modern  animals  as  far 
backward  as  we  can  through  the  study  of  fossils,  we  still  find  these 


2l8  THE  FOUNDATIONS   OF  ZOOLOGY 

lines  distinctly  laid  down.  The  Lower  Cambrian  Crustacea,  for 
example,  are  as  distinct  from  the  Lower  Cambrian  echinoderms  or 
pteropods  or  laraellibranchs  or  brachipods  as  they  are  from  those  of 
the  present  day,  but  zoology  gives  us  evidence  that  the  early  steps 
in  the  establishment  of  these  great  lines  were  taken  under  condi- 
tions which  were  essentially  different  from  those  which  have  pre- 
vailed, without  any  essential  change,  from  the  time  of  the  oldest 
fossils  to  the  present  day,  and  that  most  of  the  great  lines  of 
descent  were  represented  in  the  remote  past  by  ancestors,  which, 
living  a  different  sort  of  life,  differed  essentially,  in  structure  as 
well  as  in  habits,  from  the  representatives  of  the  same  types  which 
are  known  to  us  as  fossils. 

In  the  echinoderms  we  have  a  well-defined  type  represented 
by  abundant  fossils,  very  rich  in  living  forms,  very  diversified  in 
its  modifications,  and  therefore  well  fitted  for  use  as  an  illustration. 
This  great  stem  contains  many  classes  and  orders,  all  constructed 
on  the  same  plan,  which  is  sharply  isolated  and  quite  unlike  the 
plan  of  structure  in  any  other  group  of  animals.  All  through 
the  series  of  fossiliferous  rocks  echinoderms  are  found,  and  their 
plan  of  structure  is  always  the  same.  Paleontology  gives  us  most 
valuable  evidence  regarding  the  course  of  evolution  within  the 
limits  of  a  class,  as  in  the  crinoids  or  the  echinoids ;  but  we  appeal 
to  it  in  vain  for  light  upon  the  organization  of  the  primitive  echino- 
derm  or  for  connecting  links  between  the  classes.  To  our  ques- 
tions on  these  subjects,  and  on  the  relation  of  the  echinoderms 
to  other  animals,  paleontology  is  silent,  and  throws  them  back 
upon  us  as  unsolved  riddles. 

The  zoologist  unhesitatingly  projects  his  imagination,  held  in 
check  only  by  the  laws  of  scientific  thought,  into  the  dark  period 
before  the  times  of  the  oldest  fossils,  and  he  feels  absolutely  certain 
of  the  past  existence  of  a  stem  from  which  the  classes  of  echino- 
derms have  inherited  the  fundamental  plan  of  their  structure.  He 
affirms  with  equal  confidence  that  the  structural  changes  which 
have  separated  this  ancient  type  from  the  classes  which  we  know 
from  fossils  are  very  much  more  profound  and  extensive  than  all 
the  changes  which  each  class  has  undergone  from  the  earliest 
paleozoic  times  to  the  present  day.  He  is  also  disposed  to  assume, 
but,  as  I  shall  show,  with    much    less  reason,  that   the    amount  of 


NATURAL  SELECTION,   AND    THE  ANTIQUITY  OF  LIFE     219 

change  which  structure  has  undergone  is  an  index  to  the  length 
of  time  which  the  change  has  required,  and  that  the  period  which 
is  covered  by  the  fossiliferous  rocks  is  only  an  inconsiderable  part  of 
that  which  has  been  consumed  in  the  evolution  of  the  echinoderms. 

The  zoologist  does  not  check  the  flight  of  his  scientific  imagi- 
nation here,  however,  for  he  trusts  implicitly  to  the  embryological 
evidence  which  teaches  him  that  still  farther  back  in  the  past  all 
echinoderms  were  represented  by  a  minute  floating  animal  which 
was  not  an  echinoderm  at  all  in  any  sense  except  the  ancestral 
one,  although  it  was  distinguished  by  features  which  natural  selec- 
tion has  converted,  under  the  influence  of  modern  conditions, 
into  the  structure  of  echinoderms.  He  finds  in  the  embryology 
of  modern  echinoderms  phenomena  which  can  bear  no  interpreta- 
tion but  this,  and  he  unhesitatingly  assumes  that  they  are  an  in-- 
heritance  which  has  been  handed  down  from  generation  to  gen- 
eration through  all  the  ages  from  the  prehistoric  times  of  zoology. 

Other  groups  tell  the  same  story  with  equal  clearness.  A 
lingula  is  still  living  in  the  sand-bars  and  mud-flats  of  the  Chesa- 
peake Bay  under  conditions  which  have  not  effected  any  essen- 
tial change  in  its  structure  since  the  time  of  the  Lower  Cambrian. 
Who  can  look  at  a  living  lingula  without  being  overwhelmed 
by  the  effort  to  grasp  its  immeasurable  antiquity ;  by  the  thought 
that  while  it  has  passed  through  all  the  chances  and  changes  of 
geological  history,  the  structure  which  fitted  it  for  life  on  the  earli- 
est paleozoic  bottom  is  still  adapted  for  a  life  on  the  sands  of  the 
modern  sea-floor.'' 

The  everlasting  hills  are  the  type  of  venerable  antiquity ;  but 
lingula  has  seen  the  continents  grow  up,  and  has  maintained  its 
integrity  unmoved  by  the  convulsions  which  have  given  the  crust 
of  the  earth  its  present  form. 

As  measured  by  the  time-standards  of  the  zoologist  lingula 
itself  is  modern,  for  its  life  history  still  holds  locked  up  in  its  em- 
bryology the  record,  repeated  in  the  development  of  each  individ- 
ual, of  a  structure  and  a  habit  of  life  which  were  lost  in  the  unknown 
past  at  the  time  of  the  Lower  Cambrian,  and  it  tells  us  vaguely 
but  unmistakably  of  life  at  the  surface  of  the  primitive  ocean 
at  a  time  when  it  was  represented  by  minute  and  simple  floating 
ancestors. 


220  THE  FOUNDATIONS  OF  ZOOLOGY 

Broadly  stated,  the  history  of  each  great  line  has  been  like  that 
of  the  echinoderms  and  brachiopods.  The  oldest  pteropod  or 
lamellibranch  or  echinoderm  or  crustacean  or  vertebrate  which  we 
know  from  fossils  exhibits  its  own  type  of  structure  with  perfect 
distinctness,  and  later  influences  have  done  no  more  than  to  expand 
and  diversify  the  type,  while  anatomy  fails  to  guide  us  back  to  the 
point  where  these  various  lines  met  each  other  in  a  common  source, 
although  it  forces  us  to  believe  that  the  common  source  once  had 
an  individual  existence.  Embryology  teaches  that  each  line  once 
had  its  own  representative  at  the  surface  of  the  ocean,  and  that 
the  early  stages  in  its  evolution  have  passed  away  and  left  no  record 
in  the  rocks. 

If  we  try  to  call  before  the  mind  a  picture  of  the  land  surface 
of  the  earth  we  see  a  vast  expanse  of  verdure  stretching  from  high 
up  in  the  mountains  over  hills,  valleys,  and  plains,  and  through 
forests  and  meadows  down  to  the  sea,  with  only  an  occasional  lake 
or  broad  river  to  break  its  uniformity. 

Our  picture  of  the  ocean  is  an  empty  waste,  stretching  on  and 
on  with  no  break  in  the  monotony  except  now  and  then  a  flying- 
fish  or  a  wandering  sea-bird  or  a  floating  tuft  of  sargassum,  and 
we  never  think  of  the  ocean  as  the  home  of  vegetable  life.  It 
contains  plant-like  animals  in  abundance,  but  these  are  true  ani- 
mals and  not  plants,  although  they  are  so  like  them  in  form  and 
color.  At  Nassau,  in  the  Bahama  Islands,  the  visitor  is  taken  in 
a  small  boat,  with  windows  of  plate  glass  set  in  the  bottom,  to 
visit  the  "  sea-gardens "  at  the  inner  end  of  a  channel  through 
which  the  pure  water  from  the  open  sea  flows  between  two  coral 
islands  into  the  lagoon.  Here  the  true  reef  corals  grow  in  quiet 
water,  where  they  may  be  visited  and  examined. 

When  illuminated  by  the  vertical  sun  of  the  tropics  and  by 
the  light  which  is  reflected  back  from  the  white  bottom,  the  pure, 
transparent  water  is  as  clear  as  air,  and  the  smallest  object  forty 
or  fifty  feet  down  is  distinctly  visible  through  the  glass  bottom  of 
the  boat. 

As  this  glides  over  the  great  mushroom-shaped  coral  domes 
which  arch  up  from  the  depths,  the  dark  grottoes  between  them 
and  the  caves  under  their  overhanging  tops  are  lighted  up  by  the 
sun,    far   down    among   the    anthozoa    or   flower    animals    and   the 


NATURAL   SELECTION,   AND   THE  ANTIQUITY  OF  LIFE     22  [ 

zoophytes  or  animal  plants,  which  are  seen  through  the  waving 
thicket  of  brown  and  purple  sea-fans  and  sea-feathers  as  they 
toss  before  the  swell  from  the  open  ocean. 

There  are  miles  of  these  "sea-gardens"  in  the  lagoons  of  the 
Bahamas,  and  it  has  been  my  good  fortune  to  spend  many  months 
studying  their  wonders,  but  no  description  can  convey  any  concep- 
tion of  their  beauty  and  luxuriance.  The  general  effect  is  very 
garden-like,  and  the  beautiful  fishes  of  black  and  golden  yellow 
and  iridescent  cobalt  blue  hover  like  birds  among  the  thickets  of 
yellow  and  lilac  gorgonias. 

The  parrot  fishes  seem  to  be  cropping  the  plants  like  rabbits, 
but  more  careful  examination  shows  that  they  are  biting  off  the 
tips  of  the  gorgonias  and  branching  madrepores  or  hunting  for  the 
small  Crustacea  which  hide  in  the  thicket,  and  that  all  the  apparent 
plants  are  really  animals. 

The  delicate  star-like  flowers  are  the  vermilion  heads  of  boring 
annelids  or  the  scarlet  tentacles  of  actinias,  and  the  thicket  is 
made  up  of  pale  lavender  bushes  of  branching  madrepores,  and 
green  and  brown  and  yellow  and  olive  masses  of  brain  coral,  of 
alcyonarians  of  all  shades  of  yellow  and  purple,  lilac  and  red,  and 
of  black  and  brown  and  red  sponges.  Even  the  lichens  which 
incrust  the  rocks  are  hydroid  corals,  and  the  whole  sea-garden  is 
a  dense  jungle  of  animals,  where  plant  life  is  represented  only  by 
a  few  calcareous  algae  so  strange  in  shape  and  texture  that  they 
are  much  less-  plant-like  than  the  true  animals. 

The  scarcity  of  plant  life  becomes  still  more  notable  when  we 
study  the  ocean  as  a  whole.  On  land  herbivorous  animals  are 
always  much  more  abundant  and  proHfic  than  the  carnivora,  as 
they  must  be  to  keep  up  the  supply  of  food,  but  the  animal  life  of 
the  ocean  shows  a  most  remarkable  difference,  for  marine  animals 
are  almost  exclusively  carnivorous. 

The  birds  of  the  ocean,  the  terns,  gulls,  petrels,  divers,  cormo- 
rants, tropic  birds  and  albatrosses,  are  very  numerous  indeed,  and 
the  only  parallel  to  the  pigeon  roosts  and  rookeries  of  the  land  is 
found  in  the  dense  clouds  of  sea-birds  around  their  breeding 
grounds,  but  all  these  sea-birds  are  carnivorous,  and  even  the  birds 
of  the  seashore  subsist  almost  exclusively  upon  animals  such  as 
mollusca,  Crustacea,  and  annelids. 


222  THE  FOUNDATIONS  OF  ZOOLOGY 

The  seals  pursue  and  destroy  fishes ;  the  sea-elephants  and 
walruses  live  upon  mollusks ;  the  whales,  dolphins  and  porpoises 
and  the  marine  reptiles  all  feed  upon  animals,  and  most  of  them 
are  fierce  beasts  of  prey. 

There  are  a  few  fishes  that  pasture  in  the  fringe  of  seaweed 
which  grows  on  the  shore  of  the  ocean,  and  there  are  some  that 
browse  among  the  floating  tufts  of  algae  upon  its  surface,  but  most 
of  them  frequent  these  places  in  search  of  the  small  animals 
that  hide  among  the  plants. 

In  the  Chesapeake  Bay  the  sheepshead  browses  among  the 
algae  upon  the  submerged  rocks  and  piles  like  a  marine  sheep, 
but  its  food  is  exclusively  animal,  and  I  have  lain  upon  the  edge 
of  a  wharf  watching  it  crunch  the  barnacles  and  young  oysters 
until  the  juice  of  their  bodies  streamed  out  of  the  angles  of  its 
mouth  and  gathered  a  host  of  small  fishes  to  snatch  the  fragments 
as  they  drifted  away  with  the  tide. 

Many  important  fishes,  like  the  cod,  pasture  on  the  bottom, 
but  their  pasturage  consists  of  mollusks  and  annelids  and  Crustacea 
instead  of  plants,  and  the  vast  majority  of  sea-fishes  are  fierce 
hunters,  pursuing  and  destroying  smaller  fishes,  and  often  exhibit- 
ing an  insatiable  love  of  slaughter,  like  our  own  bluefish  and  the 
tropical  albacore  and  barracuda.  Others,  such  as  the  herring,  feed 
upon  smaller  fishes  and  the  pelagic  pteropods-  and  copepods ;  and 
others,  like  the  shad,  upon  the  minute  organisms  of  the  ocean ;  but 
all,  with  few  exceptions,  are  carnivorous.  In  the  other  great  groups 
of  marine  animals  we  find  some  scavengers,  some  which  feed  upon 
micro-organisms,  and  others  which  hunt  and  destroy  each  other, 
but  there  is  no  group  of  marine  animals  that  corresponds  to  the 
herbivora  and  rodents  and  the  plant-eating  birds  and  insects  of 
the  land. 

There  is  so  much  room  in  the  vast  spaces  of  the  ocean,  and 
so  much  of  it  is  hidden,  that  it  is  only  when  surface  animals  are 
gathered  together  that  the  abundance  of  marine  life  becomes  visi- 
ble and  impressive ;  but  some  faint  conception  of  the  boundless 
wealth  of  the  ocean  may  be  gained  by  observing  the  quickness 
with  which  marine  animals  become  crowded  together  at  the  sur- 
face in  favorable  weather.  On  a  cruise  of  more  than  two  weeks 
along  the  edge  of   the  Gulf    Stream  I  was  surrounded  continually 


NATURAL   SELECTION,   AND    THE  ANTIQUITY  OF  LIFE     223 

night  and  day  by  a  vast  army  of  dark-brown  jelly-fish  {Linergcs 
merciitid),  whose  dark  color  made  them  very  conspicuous  in  the 
clear  water.  We  could  see  them  at  a  distance  from  the  vessel, 
and  at  noon,  when  the  sun  was  overhead,  we  could  look  down  to 
a  great  depth  through  the  centre-board  well,  and  everywhere,  to  a 
depth  of  fifty  or  sixty  feet,  we  could  see  them  drifting  by  in  a 
steady  procession  like  motes  in  a  sunbeam.  We  cruised  through 
them  for  more  than  five  hundred  miles  and  we  tacked  back  and 
forth  over  a  breadth  of  almost  a  hundred  miles,  and  found  them 
everywhere  in  such  abundance  that  there  were  some  in  every 
bucketful  of  water  we  dipped  up ;  nor  is  this  abundance  of  life 
restricted  to  tropical  waters,  for  Haeckel  tells  us  that  he  met 
with  such  enormous  masses  of  Limacina  to  the  northwest  of  Scot- 
land that  each  bucket  of  water  contained  thousands.  The  ten- 
dency to  gather  in  crowds  is  not  restricted  to  the  smaller  animals, 
and  many  species  of  raptorial  fishes  are  found  in  densely  packed 
banks. 

The  fishes  in  a  school  of  mackerel  are  as  numerous  as  the 
birds  in  a  flight  of  wild  pigeons,  and  we  are  told  of  one  school 
which  was  a  windrow  of  fish  half  a  mile  wide  and  at  least  twenty 
miles  long.  But  while  pigeons  are  plant  eaters,  the  mackerel  are 
rapacious  hunters,  pursuing  and  devouring  the  herrings  as  well  as 
other  animals. 

Herring  swarm  like  locusts,  and  a  herring  bank  is  almost  a 
solid  wall.  In  1879  three  hundred  thousand  river  herring  were 
landed  in  a  single  haul  of  the  seine  in  Albemarle  Sound ;  but  the 
herring  are  also  carnivorous,  each  one  consuming  myriads  of  cope- 
pods  every  day. 

In  spite  of  this  destruction  and  the  ravages  of  armies  of 
medusae  and  siphonophores  and  pteropods,  the  fertility  of  the  cope- 
pods  is  so  great  that  they  are  abundant  in  all  parts  of  the  ocean, 
and  they  are  met  with  in  numbers  that  exceed  our  power  of 
comprehension.  On  one  occasion  the  Challenger  steamed  for  two 
days  through  a  dense  cloud  formed  of  a  single  species,  and  they 
are  found  in  all  latitudes,  from  the  arctic  regions  to  the  equator, 
in  masses  which  discolor  the  water  for  miles.  We  know,  too,  that 
they  are  not  restricted  to  the  surface,  and  that  the  banks  of  cope- 
pods    are    sometimes    more    than    a    mile    thick.     When  we  reflect 


224  THE  FOUNDATION'S   OF  ZOOLOGY 

that  thousands  would  find  ample  room  and  food  in  a  pint  of  water, 
one  can  form  some  faint  conception  of   their  universal  abundance. 

The  orsranisms  which  are  visible  in  the  water  of  the  ocean  and 
on  the  sea-bottom  are  almost  universally  engaged  in  devouring 
each  other,  and  many  of  them,  like  the  bluefish,  are  never  satis- 
fied with  slaughter,  but  kill  for  mere  sport. 

Insatiable  rapacity  must  end  in  extermination  unless  there  is 
some  unfailing  supply,  and  as  we  find  no  visible  supply  in  the 
water  of  the  ocean  we  must  seek  it  with  a  microscope,  which 
shows  us  a  wonderful  fauna  made  up  of  innumerable  larvae  and 
embryos  and  small  animals,  but  these  things  cannot  be  the  food 
supply  of  the  ocean,  for  no  carnivorous  animal  could  subsist  very 
long  by  devouring  its  own  children.  The  total  amount  of  these 
animals  is  inconsiderable,  however,  when  compared  with  the  abun- 
dance of  a  few  forms  of  protozoa  and  protophytes,  and  both  obser- 
vation and  deduction  teach  that  the  most  important  element  in 
marine  life  consists  of  some  half-dozen  types  of  protozoa  and 
unicellular  plants ;  of  globigerina  and  radiolarians,  and  of  trichodes- 
mium,  pyrocystis,  protococcus  and  the  coccospheres,  rhabdospheres, 
and  diatoms. 

Modern  microscopical  research  has  shown  that  these  simple 
plants,  and  the  globigerinae  and  radiolarians  which  feed  upon  them, 
are,  so  abundant  and  prolific  that  they  meet  all  demands  and  supply 
the  food  for  all  the  animals  of  the  ocean.  This  is  the  fundamental 
conception  of  marine  biology.  The  basis  of  all  the  life  in  the  modern 
ocean  is  found  in  the  micro-organisms  of  the  surface. 

This  is  not  all.  The  simplicity  and  abundance  of  the  micro- 
scopic forms  and  their  importance  in  the  economy  of  nature  show 
that  the  organic  world  has  gradually  taken  shape  around  them  as 
its  centre  or  starting-point,  and  has  been  controlled  by  them. 
They  are  not  only  the  fundamental  food  supply,  but  the  primeval 
supply,  which  has  determined  the  whole  course  of  the  evolution  of 
marine  life. 

The  pelagic  plant  life  of  the  ocean  has  retained  its  primitive 
simplicity  on  account  of  the  very  favorable  character  of  its  envi- 
ronment, and  the  higher  rank  of  the  littoral  vegetation  and  that  of 
the  land  is  the  result  of  hardship. 

On  land  the  mineral  elements  of  plant  food  are  slowly  supplied, 


NATURAL   selection;   AND    THE  ANTIQUITY  OF  LIFE     22$ 

as  the  rains  dissolve  them ;  Kmited  space  brings  crowding  and  com- 
petition for  this  scanty  supply ;  growth  is  arrested  for  a  great  part 
of  each  year  by  drought  or  cold;  the  diversity  of  the  earth's  sur- 
face demands  diversity  of  structure  and  habit,  and  the  great  size 
and  complicated  structure  of  terrestrial  plants  are  adaptations  to 
these  conditions  of    hardship. 

At  the  surface  of  the  ocean  the  abundance  and  uniform  distri- 
bution of  mineral  food  in  solution,  the  area  which  is  available  for 
plants,  the  volume  of  sunlight  and  the  uniformity  of  the  tempera- 
ture are  all  favorable  to  the  growth  of  plants,  and  as  each  plant  is 
bathed  on  all  sides  by  a  nutritive  fluid,  it  is  advantageous  for  the 
new  plant-cells  which  are  formed  by  cell-multiplication,  to  separate 
from  each  other  as  soon  as  possible,  in  order  to  expose  the  whole 
of  their  surface  to  the  water.  Cell-aggregation,  the  first  step 
toward  higher  organization,  is  therefore  disadvantageous  to  the 
pelagic  plants,  and  as  the  environment  at  the  surface  of  the  ocean 
is  so  monotonous,  there  is  little  opportunity  for  an  aggregation  of 
cells  to  gain  any  compensating  advantage  by  seizing  upon  a  more 
favorable  habitat.  The  pelagic  plants  have  retained  their  primi- 
tive simplicity,  and  the  most  distinctive  peculiarity  of  the  micro- 
scopic food  supply  of  the  ocean  is  the  very  small  number  of  forms 
which  make  up  the  enormous  mass  of  individuals. 

All  the  animals  of  the  ocean  are  dependent  upon  this  supply 
of  microscopic  food,  and  many  of  them  are  adapted  for  preying 
upon  it  directly,  but  a  review  of  the  animal  kingdom  will  show 
that  no  highly  organized  animal  has  ever  been  evolved  at  the  sur- 
face of  the  ocean,  although  all  depend  upon  the  food  supply  of 
the  surface. 

The  animals  which  now  find  their  home  in  the  open  waters  of 
the  ocean  are,  almost  without  exception,  descendants  of  forms 
which  lived  upon  or  near  the  bottom,  or  along  the  seashore,  or 
upon  the  land,  and  all  the  exceptions  are  simple  animals  of  minute 
size.  A  review  of  the  whole  animal  kingdom  would  take  more 
space  than  we  can  spare,  but  it  would  show  that  the  evidence  from 
embryology,  from  comparative  anatomy,  and  from  paleontology 
all  bears  in  the  same  direction  and  proves  that  every  large  and 
highly  organized  animal  in  the  open  ocean  is  descended  from 
ancestors  whose  home  was  not  open  water,  but  solid  ground,  either 
Q 


226  THE  FOUNDATIONS  OF  ZOOLOGY 

on  the  bottom  or  on  the  shore.  Embryology  also  gives  us  good 
ground  for  believing  that  all  these  animals  are  still  more  remotely 
descended  from  minute  and  simple  pelagic  ancestors,  and  .that 
the  history  of  all  the  highly  organized  inhabitants  of  the  water 
has  followed  a  roundabout  path  from  the  surface  to  the  bottom 
and  then  back  into  the  water.  When  this  fact  is  seen  in  all  its 
bearings,  and  its  full  significance  is  grasped,  it  is  certainly  one  of 
the  most  notable  and  instructive  features  of  evolution. 

The  food  supply  of  marine  animals  consists  of  a  few  species 
of  microscopic  organisms  which  are  inexhaustible  and  the  only 
source  of  food  for  all  the  inhabitants  of  the  ocean.  The  supply 
is  primeval  as  well  as  inexhaustible,  and  all  the  life  of  the  ocean 
has  gradually  taken  shape  in  direct  dependence  upon  it.  In  view 
of  these  facts  we  cannot  but  be  profoundly  impressed  by  the 
thought  that  all  the  highly  organized  marine  animals  are  products 
of  the  bottom  or  the  shore  or  the  land,  and  that  while  the  largest 
animals  on  earth  are  pelagic,  the  few  that  are  primitively  pelagic 
are  small  and  simple.  The  reason  is  obvious.  The  conditions  of 
life  at  the  surface  are  so  easy  that  there  is  little  fierce  competition, 
and  the  inorganic  environment  is  so  simple  that  there  is  little 
chance  for  diversity  of  habits. 

The  growth  of  terrestrial  plants  is  limited  by  the  scarcity  of 
food,  but  there  is  no  such  limit  to  the  growth  of  pelagic  plants 
or  the  animals  which  feed  on  them,  and  while  the  balance  of  life 
is  no  doubt  adjusted  by  competition  for  food,  this  is  never  very 
fierce,  even  at  the  present  day,  when  the  ocean  swarms  with  highly 
organized  wanderers  from  the  bottom  and  the  shore.  Even  now 
the  destruction  or  escape  of  a  microscopic  pelagic  organism  de- 
pends upon  the  accidental  proximity  or  remoteness  of  an  enemy 
rather  than  upon  defence  or  protection,  and  survival  is  determined 
by  space  relations  rather  than  a  struggle  for  existence. 

The  abundance  of  food  is  shown  by  the  ease  with  which  wan- 
derers from  the  land,  like  sea-birds,  find  places  for  themselves  in  the 
ocean,  and  the  rapidity  with  which  they  spread  over  its  whole  extent. 

As  a  marine  animal  the  insect  Halobates  must  be  very  modern 
as  compared  with  most  pelagic  forms,  yet  it  has  spread  over  all 
tropical  and  subtropical  seas,  and  it  may  always  be  found  skim- 
ming over  the  surface  of  mid-ocean  as  much  at  home  as  a  Gerris 


NATURAL   SELECTION,   AND    THE  ANTIQUITY  OF  LIFE     227 

in  a  pond.  I  have  never  found  it  absent  in  the  Gulf  Stream  when 
conditions  were  favorable  for  collecting. 

The  easy  character  of  pelagic  life  is  shown  by  the  fact  that 
the  larvae  of  innumerable  animals  from  the  bottom  and  the  shore 
have  retained  their  pelagic  habit,  and  I  shall  soon  give  reasons 
for  believing  that  the  larva  of  a  shore  animal  is  safer  at  sea  than 
near  the  shore. 

There  was  little  opportunity  in  the  primitive  pelagic  fauna 
and  flora  for  an  organism  to  gain  superiority  by  seizing  upon  an 
advantageous  site  or  by  acquiring  peculiar  habits,  for  one  place  was 
like  another,  and  peculiar  habits  could  count  for  little  in  compari- 
son with  accidental  space  relations.  After  the  fauna  of  the  sur- 
face had  been  enriched  by  all  the  marine  animals  which  have 
become  secondarily  adapted  to  pelagic  life,  competition  with  those 
improved  form's  brought  about  improvements  in  those  which  were 
strictly  pelagic  in  origin,  like  the  siphonophores,  and  those  wan- 
derers from  the  bottom  introduced  another  factor  into  the  evolu- 
tion of  pelagic  life,  for  their  bodies  have  been  utilized  for  protection 
or  concealment  and  in  other  ways,  and  we  now  have  fishes  which 
hide  in  the  poison  curtain  of  Physalia,  Crustacea  which  live  in  the 
pharynx  of  Salpa  or  in  the  mouth  of  the  menhaden,  barnacles  and 
sucking  fish  fastened  to  whales  and  turtles,  besides  a  host  of  exter- 
nal and  internal  parasites.  The  primitive  ocean  furnished  no  such 
opportunity,  and  the  conditions  of  pelagic  life  must  at  first  have 
"been  very  simple,  and  while  competition  was  not  entirely  absent 
the  possibilities  of  evolution  must  have  been  extremely  limited  and 
the  progress  of  divergent  modification  very  slow  so  long  as  all 
life  was  restricted  to  the  waters  of  the  ocean. 

There  can  be  no  doubt  that  floating  life  was  abundant  for  a 
long  period  when  the  bottom  was  uninhabited.  The  slow  geologi- 
cal changes  by  which  the  earth  gradually  assumed  its  present 
character  present  a  boundless  field  for  speculation,  but  there  can 
be  no  doubt  that  the  surface  of  the  primeval  ocean  became  fit  for 
living  things  long  before  the  deeper  waters  or  the  sea-floor,  and 
during  this  period  the  proper  conditions  for  the  production  of 
large  and  complicated  organisms  did  not  exist,  and  even  after  the 
total  amount  of  life  had  become  very  great  it  must  have  consisted 
of  organisms  of  small  size  and  simple  structure. 


228  THE  FOUNDATIONS   OF  ZOOLOGY 

Marine  life  is  older  than  terrestrial  life,  and  as  all  marine  life 
has  shaped  itself  in  relation  to  the  pelagic  food  supply,  this  itself 
is  the  only  form  of  life  which  is  independent,  and  it  must  there- 
fore be  the  oldest.  There  must  have  been  a  long  period  in  prime- 
val times  when  there  was  a  pelagic  fauna  and  flora  rich  beyond 
hmit  in  individuals,  but  made  up  of  only  a  few  simple  types. 
During  this  time  the  pelagic  ancestors  of  all  the  great  groups  of 
animals  were  slowly  evolved,  as  well  as  other  forms  which  have 
left  no  descendants.  So  long  as  life  was  restricted  to  the  surface 
no  great  or  rapid  advancement,  through  the  influences  which  now 
modify  species,  was  possible,  and  we  know  of  no  other  influences 
which  might  have  replaced  them.  We  are  therefore  forced  to  be- 
lieve that  the  differentiation  and  improvement  of  the  primitive 
flora  and  fauna  were  slow,  and  that,  for  a  vast  period  of  time, 
life  consisted  of  an  innumerable  multitude  of  minute  and  simple 
pelagic  organisms.  During  the  time  which  it  took  to  form  the 
thick  beds  of  older  sedimentary  rocks  the  physical  conditions  of 
the  ocean  gradually  took  their  present  form,  and  during  a  part, 
at  least,  of  this  period  the  total  amount  of  life  in  the  ocean  may 
have  been  very  nearly  as  great  as  it  is  now  without  leaving  any 
permanent  record  of  its  existence,  for  no  rapid  advance  took 
place  until  the  advantages  of  life  on  the  bottom    were    discovered. 

We  must  not  think  of  the  populating  of  the  bottom  as  a 
physical  problem,  but  as  discovery  and  colonization,  very  much 
like  the  colonization  of  islands.  Physical  conditions  for  a  long 
time  made  it  impossible,  but  its  initiation  was  the  result  of  bio- 
logical influences,  and  there  is  no  reason  why  its  starting-point 
should  necessarily  be  the  point  where  the  physical  obstacles  first 
disappeared.  It  is  useless  to  speculate  upon  the  nature  of  the 
physical  obstacles ;  there  is  reason  to  think  one  of  them,  probably 
an  important  one,  was  the  deficiency  of  o.xygen  in  deep  water. 

Whatever  their  character  may  have  been,  they  were  all,  no 
doubt,  of  such  a  nature  that  thev  first  disappeared  in  the  shallow 
water  around  the  coast,  but  it  is  not  probable  that  bottom  life 
was  first  established  in  shallow  water,  or  before  the  physical  con- 
ditions had  become  favorable  at  considerable  depths. 

The  sediment  near  the  shore  is  destructive  to  most  surface 
animals,    and    recent    explorations    have    shown    that    a    stratum    of 


iVATURAL   selection;   AND    THE  ANTIQUITY  OF  LIFE     229 

water  of  very  great  thickness  is  necessary  for  the  complete  de- 
velopment of  the  floating  microscopic  fauna  and  flora,  and  it  is  a 
mistake  to  picture  them  as  confined  to  a  thin  surface  stratum. 
Pelagic  plants  probably  flourished  as  far  down  as  light  penetrates, 
and  pelagic  animals  are  abundant  at  very  great  depths.  As  the 
earliest  bottom  animals  must  have  depended  directly  upon  the 
floating  organisms  for  food,  it  is  not  probable  that  they  first  estab- 
lished themselves  in  shallow  water,  where  the  food  supply  is  both 
scanty  and  mixed  with  sediment ;  nor  is  it  probable  that  their  es- 
tablishment was  delayed  until  the  great  depths  had  become  favor- 
able to  life. 

The  belts  around  elevated  areas  far  enough  from  shore  to  be 
free  from  sediment,  and  deep  enough  to  permit  the  pelagic  fauna 
to  reach  its  full  development  above  them,  are  the  most  favorable 
spots,  and  paleontological  evidence  shows  that  they  were  seized 
upon  very  early  in  the  history  of  life  on  the  bottom. 

It  is  probable  that  colony  after  colony  was  established  on  the 
bottom  and  afterwards  swept  away  by  geological  change  like  a 
cloud  before  the  wind,  and  that  the  bottom  fauna  which  we  know 
was  not  the  first.  Colonies  which  started  in  shallow  water  were 
exposed  to  accidents  from  which  those  in  great  depths  were  free, 
and  in  view  of  our  knowledge  of  the  permanency  of  the  sea-floor 
and  of  the  broad  outlines  of  the  continents,  it  is  not  impossible 
that  the  first  fauna  which  became  established  in  the  deep  zone 
around  the  continents  may  have  persisted  and  given  rise  to  modern 
animals.  However  this  may  be,  we  must  regard  this  deep  zone 
as  the  birthplace  of  the  fauna  which  has  survived,  as  the  ancestral 
home  of  all  the  improved  metazoa. 

The  effect  of  life  upon  the  bottom  is  more  interesting  than 
the  place  where  it  began,  and  we  are  now  to  consider  its  influence 
upon  animals,  all  whose  ancestors  and  competitors  and  enemies 
had  previously  been  pelagic.  The  cold,  dark,  silent,  quiet  depths 
of  the  sea  are  monotonous  compared  with  the  land,  but  they  intro- 
duced many  new  factors  into  the  course  of  organic  evolution. 

It  is  doubtful  whether  the  animals  which  first  settled  on  the 
bottom  secured  any  more  food  than  the  floating  ones,  but  they 
undoubtedly  obtained  it  with  less  effort,  and  were  able  to  devote 
their  superfluous  energy  to  growth  and  to  multiplication,  and  thus 


230  THE  FOUNDATIONS  OF  ZOOLOGY 

to  become  larger  and  to  increase  faster  than  pelagic  animals. 
Their  sedentary  life  must  have  been  favorable  to  both  sexual  and 
asexual  multiplication,  and  the  tendency  to  increase  by  budding 
must  have  been  quickly  rendered  more  active,  and  one  of  the  first 
results  of  life  on  the  bottom  must  have  been  to  promote  the  ten- 
dency to  form  connected  cormi,  and  to  retain  the  connection 
between  the  parent  and  the  bud  until  the  latter  was  able  to  obtain 
its  own  food  and  to  care  for  itself.  The  animals  which  first 
acquired  the  habit  of  resting  on  the  bottom  soon  began  to  multiply 
faster  than  their  swimming  allies,  and  their  asexually  produced 
progeny,  remaining  for  a  longer  time  attached  to  and  nourished 
by  the  parent  stock,  were  much  more  favorably  placed  for  rapid 
growth.  As  the  animals  of  the  bottom  live  on  a  surface,  or  at 
least  a  thin  stratum,  while  swimming  animals  are  distributed 
through  solid  space,  the  rapid  multiplication  of  bottom  animals 
must  soon  have  led  to  crowding  and  to  competition,  and  it  quickly 
became  harder  and  harder  for  new  forms  from  the  open  water  to 
force  themselves  in  among  the  old  ones,  and  colonization  soon 
came  to  an  end. 

The  great  antiquity  of  all  the  types  of  structure  which  are 
represented  among  modern  animals  is  therefore  what  we  should 
expect ;  for,  after  the  foundation  of  the  fauna  of  the  bottom  was 
laid,  it  became,  and  has  ever  since  remained,  difficult  for  new  forms 
to  establish  themselves. 

Most  of  our  knowledge  of  the  sea-bottom  is  from  three  sources : 
from  dredgings  and  other  explorations,  from  rocks  which  were 
formed  beyond  the  immediate  influence  of  continents,  and  from 
the  patches  of  the  bottom  fauna  which  have  gradually  been 
brought  near  its  surface  by  the  growth  of  coral  reefs;  and  from 
all  these  sources  we  have  testimony  to  the  density  of  the  crowd 
of  animals  on  favorable  spots.  Deep-sea  explorations  give  only 
the  most  scanty  basis  for  a  picture  of  the  sea-bottom,  but  they 
show  that  animal  life  may  thrive  with  the  dense  luxuriance  of 
tropical  vegetation,  and  Sir  Wyville  Thomson  says  he  once  brought 
up  at  one  time  on  a  tangle,  which  was  fastened  to  a  dredge,  over 
twenty  thousand  specimens  of  a  single  species  of  sea-urchin.  The 
number  of  remains  of  paleozoic  crinoids  and  brachiopods  and  trilo- 
bites  which  are  crowded  into  a  single  slab  of  fine-grained  limestone 


NATURAL   SELECTION,   AND    THE  ANTIQUITY  OF  LIFE     23 1 

is  most  astounding,  and  it  testifies  most  vividly  and  forcibly  to 
the  wealth  of  life  on  the  old  sea-floor. 

No  description  can  convey  any  adequate  conception  of  the 
boundless  luxuriance  of  a  coral  island,  but  nothing  else  gives  such 
a  vivid  picture  of  the  capacity  of  the  sea-floor  for  supporting  life. 
Marine  plants  are  not  abundant  on  coral  islands,  and  the  animals 
depend  either  directly  or  indirectly  upon  the  pelagic  food  supply, 
so  that  their  life  is  the  same  in  this  respect  as  that  of  animals  in 
the  deep  sea  far  from  land. 

The  abundant  life  is  not  restricted  to  the  growing  edge  of  the 
reef,  and  the  inner  lagoons  are  often  like  crowded  aquaria.  At 
Nassau  my  party  of  eight  persons  found  so  much  to  study  on  a 
little  reef  in  a  lagoon  close  to  our  laboratory,  that  we  discovered 
novelties  every  day  for  four  months,  and  our  explorations  seldom 
carried  us  beyond  this  little  tract  of  bottom.  Every  inch  of  the 
bottom  was  carpeted  with  living  animals,  while  others  were  darting 
about  among  the  corals  and  gorgonias  in  all  directions ;  but  this 
was  not  all,  for  the  solid  rock  was  honeycombed  everywhere  by 
tubes  and  burrows,  and  when  broken  to  pieces  with  a  hammer 
each  mass  of  coral  gave  us  specimens  of  nearly  every  great  group 
in  the  animal  kingdom.  Fishes,  Crustacea,  annelids,  mollusca, 
echinoderms,  hydroids,  and  sponges  could  be  picked  out  of  the 
fragments,  and  the  abundance  of  life  inside  the  solid  rock  was 
most  wonderful. 

The  absence  of  pelagic  life  in  the  landlocked  water  of  coral 
islands  is  as  impressive  and  noteworthy  as  the  luxuriance  of  life 
upon  and  near  the  bottom. 

On  my  first  visit  to  the  Bahama  Islands  I  was  sadly  disap- 
pointed by  the  absence  of  pelagic  animals  where  all  the  condi- 
tions seemed  to  be  peculiarly  favorable. 

The  deep  ocean  is  so  near  that,  as  one  cruises  through  the 
inner  sounds  past  the  openings  between  the  islets  which  form 
the  outer  barrier,  the  deep  blue  water  of  mid-ocean  is  seen  to 
meet  the  white  sand  of  the  beach,  and  soundings  show  that  the 
outer  edge  is  a  precipice  as  high  as  the  side  of  Chimborazo  and 
much  steeper. 

Nowhere  else  in  the  world  is  the  pure  water  of  the  deep  sea 
found  nearer  land  or  more  free   from  sediment,  and   on   the   day.'] 


232  THE  FOUNDATIONS   OF  ZOOLOGY 

when  the  weather  was  favorable  for  outside  collecting  we  found 
siphonophores  and  pteropods,  pelagic  mollusks  and  Crustacea  and 
tunicates  and  all  sorts  of  pelagic  larvae  in  great  abundance  in  the 
open  water  just  outside  the  inlets. 

Inside  the  barrier  the  water  was  always  calm,  and  day  after 
day  it  was  as  smooth  as  the  surface  of  an  inland  lake.  When  I 
first  entered  one  of  these  beautiful  sounds,  where  the  calm,  trans- 
parent water  stretches  as  far  as  the  eye  can  reach,  while  new 
beauties  of  islets  and  winding  channels  open  before  one  as  those 
which  are  passed  fade  away  on  the  horizon,  I  felt  sure  that  I  had 
at  last  found  a  place  where  the  pelagic  fauna  of  mid-ocean  could 
be  gathered  at  our  door  and  studied  on  shore.  The  water  proved 
to  be  not  only  as  pure  as  air  but  almost  as  empty.  At  high  water 
we  sometimes  captured  a  few  pelagic  animals  near  the  inlets,  but 
we  dragged  our  surface  nets  through  the  sounds  day  after  day 
only  to  find  them  as  clean  as  if  they  had  been  hung  in  the  wind 
to  dry.  The  water  in  which  we  washed  them  usually  remained 
as  pure  and  empty  as  if  it  had  been  filtered,  and  we  often  returned 
from  our  towing  expeditions  without  even  a  copepod  or  a  zoea  or 
a  pluteus. 

The  absence  of  the  floating  larvae  is  most  remarkable,  for 
the  sounds  swarm  with  bottom  animals  which  give  birth  every 
day  to  millions  of  swimming  larvae.  The  mangrove  swamps  and 
the  rocky  shores  are  fairly  alive  with  crabs  carrying  eggs  in  all 
stages  of  development,  and  the  boat  passes  over  great  black 
patches  of  sea-urchins  crowded  together  by  thousands.  The  num- 
ber of  animals  engaged  in  laying  their  eggs  or  hatching  their 
young  is  infinite,  yet  we  rarely  captured  any  larvae  in  the  tow  net, 
and  most  of  these  we  did  find  were  well  advanced  and  nearly 
through  their  larval  life. 

It  is  often  said  that  the  water  of  coral  sounds  is  too  full  of 
lime  to  be  inhabited  by  the  animals  of  the  open  ocean,  but  this  is 
a  mistake,  for  the  water  is  perfectly  fit  for  supporting  the  most 
delicate  and  sensitive  animals,  and  those  which  we  caught  out- 
side lived  in  the  house  in  water  from  the  sounds  better  than  in 
any  other  place  where  I  ever  tried  to  keep  them,  for  instead 
of  being  injurious,  the  pure  water  of  coral  sounds  is  peculiarly 
favorable  for  use  in  aquaria  for  surface  animals. 


NATURAL   SELECTION,   AND   THE  ANTIQUITY  OF  LIFE     233 

The  scarcity  of  floating  organisms  can  have  only  one  explana- 
tion. They  are  eaten  up,  and  competition  for  food  is  so  fierce 
that  nearly  every  organism  which  is  swept  in  by  the  tide  and 
nearly  every  larva  which  is  born  in  the  sounds  is  snatched  by 
the  tentacles  around  some    hungry  mouth. 

Nothing  could  illustrate  the  fierceness  of  the  struggle  for 
food  among  the  animals  on  a  crowded  sea-bottom  more  vividly 
than  the  emptiness  of  the  water  in  coral  sounds  where  the  bot- 
tom is  practically  one  enormous  mouth.  The  only  larvae  which 
have  much  chance  to  establish  themselves  for  life  are  those  which 
are  so  fortunate  as  to  be  swept  out  into  the  open  ocean,  where 
they  can  complete  their  larval  life  under  the  milder  competition  of 
the  pelagic  fauna,  and  while  it  is  usually  stated  that  the  larvae 
of  bottom  animals  have  retained  the  pelagic  habit  for  the  purpose 
of  distributing  the  species,  it  is  more  probable  that  it  has  been 
retained  on  account  of  its  comparative  safety. 

These  facts  show  that  competition  must  have  come  quickly 
after  the  establishment  of  the  first  fauna  on  the  bottom,  and  that 
it  soon  became  very  rigorous  and  led  to  severe  selection  and 
rapid  modification ;  and  we  must  also  remember  that  life  on  the 
bottom  brought  with  it  many  new  opportunities  for  divergent 
specialization  and  improvement.  .  The  increase  in  size  which  came 
with  economy  of  energy  increased  the  possibilities  of  variation 
and  led  to  the  natural  selection  of  peculiarities  which  improved 
the  efficacy  of  the  various  parts  of  the  body  in  their  functions 
of  relation  to  each  other,  and  this  has  been  an  important  factor 
in  the  evolution  of  complicated  organisms. 

The  new  mode  of  life  also  permitted  the  acquisition  of  pro- 
tective shells,  hard-supporting  skeletons,  and  other  imperishable 
parts,  and  it  is  therefore  probable  that  the  history  of  evolution  in 
later  times  gives  no  index  as  to  the  period  which  was  required 
to  evolve  from  small,  simple  pelagic  ancestors  the  oldest  animals 
which  were  likely  to  be  preserved  as  fossils. 

Life  on  the  bottom  also  introduced  another  important  evolu- 
tionary influence  —  competition  between  blood-relations.  In  those 
animals  which  we  know  most  intimately,  divergent  modification, 
with  the  extinction  of  connecting  forms,  results  from  the  fact 
that  the  fiercest  competitors  of    each  animal  are   its   closest   allies, 


234  THE  FOUNDATIONS   OF  ZOOLOGY 

which,  having  the  same  habits,  living  upon  the  same  food,  and 
avoiding  enemies  in  the  same  way,  are  constantly  striving  to 
hold  exclusive  possession  of  all  that  is  essential  to  their  welfare. 

When  a  stock  gives  rise  to  two  divergent  branches,  each  es- 
capes competition  with  the  other  so  far  as  they  differ  in  struct- 
ure or  habits,  while  the  parent  stock  competing  with  both  at  a 
disadvantage  is  exterminated. 

Among  the  animals  which  we  know  best,  evolution  leads  to  a 
branching  tree-like  genealogy,  with  the  topmost  twigs  represented 
by  living  animals,  while  the  rest  of  the  tree  is  buried  in  the  dead 
past.  The  connecting  form  between  two  species  must  therefore 
be  sought  in  the  records  of  the  past  or  reconstructed  by  compari- 
son. Even  at  the  present  day  things  are  somewhat  different  in 
the  open  ocean,  and  they  must  have  been  very  different  in  the 
primitive  ocean,  for  a  pelagic  animal  has  no  fixed  home,  one  local- 
ity is  like  another,  and  the  competitors  and  enemies  of  each  indi- 
vidual are  determined  in  great  part  by  accidents.  We  accordingly 
find,  even  now,  that  the  evolution  of  pelagic  animals  is  often 
linear  instead  of  divergent,  and  ancient  forms,  such  as  the  sharks, 
often  live  on  side  by  side  with  the  later  and  more  evolved  forms. 
The  radiolarians  and  medusae  and  siphonophores  furnish  many 
well-known  illustrations  of  this  feature  of  pelagic  life. 

No  naturalist  is  surprised  to  find  in  the  South  Pacific  or  in  the 
Indian  Ocean  a  Salpa  or  a  pelagic  crustacean  or  a  surface  fish  or 
a  whale  which  was  previously  known  only  from  the  North  At- 
lantic, and  the  list  of  species  of  marine  animals  which  are  found 
in  all  seas  is  a  very  long  one.  The  fact  that  pelagic  animals  are 
so  independent  of  those  laws  of  geographical  distribution  which 
limit  land  animals  is  additional  evidence  of  the  easy  character  of 
the  conditions  of  pelagic  life. 

One  of  the  first  results  of  life  on  the  bottom  was  to  increase 
asexual  multiplication  and  to  lengthen  the  time  during  which 
buds  remain  united  to  and  nourished  by  their  parents,  and  to 
crowd  individuals  of  the  same  species  together  and  to  cause  com- 
petition between  relations.  We  have  in  this  and  other  obvious 
peculiarities  of  life  on  the  bottom  a  sufficient  explanation  of  the 
fact  that  since  the  first  establishment  of  the  bottom  fauna,  evolu- 
tion has  resulted  in  the  elaboration  and  divergent  specialization  of 


NATURAL  SELECTION,   AND   THE  ANTIQUITY  OF  LIFE     235 

the  types  of  structure  which  were  already  established,  rather  than 
the  production  of  new  types. 

Another  result  of  the  struggle  for  existence  on  the  bottom  was 
the  escape  of  varieties  from  competition  with  their  allies  by  flight 
from  the  crowded  spots  and  a  return  to  the  open  water  above ; 
just  as  in  later  times  the  whales  and  sea-birds  have  gone  back 
from  the  land  to  the  ocean. 

These  emigrants,  like  the  civilized  men  who  invade  the  homes 
of  peaceful  islanders,  brought  with  them  the  improvements  which 
had  come  from  fierce  competition,  and  they  have  carried  every- 
thing before  them  and  produced  a  great  change  in  the  pelagic 
fauna. 

The  rapid  intellectual  development  which  has  taken  place 
among  the  mammals  since  the  Middle  Tertiary,  and  the  rapid 
structural  changes  which  took  place  in  animals  and  plants  when 
the  land  fauna  and  flora  were  established,  are  well  known,  but  the 
fact  that  the  discovery  of  the  bottom  initiated  a  much  earlier  and 
probably  more  important  era  of  rapid  development  in  the  forms  of 
animal  life  has  never  been   pointed  out. 

If  this  view  is  correct,  the  primitive  life  of  the  bottom  must 
have  had  the  following  characteristics :  — 

(i)  It  was  entirely  animal,  without  plants,  and  it  at  first  de- 
pended directly  upon  the  pelagic  food  supply. 

(2)  It  was  established  around  elevated  areas  in  water  deep 
enough  to  be  beyond  the  influence  of  the  shore. 

(3)  The  great  groups  of  animals  were  rapidly  established  from 
pelagic  ancestors. 

(4)  The  animals  of  the  bottom  rapidly  increased  in  size  and 
hard  parts  were  quickly  acquired. 

(5)  The  bottom  fauna  soon  produced  progressive  development 
among  pelagic  animals. 

(6)  After  the  establishment  of  the  fauna  of  the  bottom,  elabo- 
ration and  differentiation  among  the  representatives  of  each  primi- 
tive type  soon  set  in  and  led  to  the  extinction  of  connecting 
forms. 

Many  of  the  oldest  fossils  like  the  pteropods  are  the  modified 
descendants  of  ancestors  with  hard  parts,  and  there  is  no  reason 
to  suppose  that  the  first  animals  which  were  capable  of  preserva- 


236  THE  FOUNDATIONS  OF  ZOOLOGY 

tion  as  fossils  have  been  discovered,  but  it  is  interesting  to  note 
that  the  oldest  known  fauna  is  an  unmistakable  approximation  to 
the  primitive  fauna  of  the  bottom. 

The  Lower  Cambrian  fossils  are  distributed  through  strata 
more  than  two  miles  thick,  some,  at  least,  of  them  showing  by  their 
fine  grain,  and  by  the  perfect  preservation  of  tracks  and  burrows 
which  were  made  in  soft  mud,  and  of  soft  animals  like  jelly-fish, 
that  they  were  deposited  in  water  of  considerable  depth.  The 
sediment  was  laid  down  slowly  and  gently  in  water  so  deep  as  to 
be  free  from  disturbance  and  under  conditions  so  favorable  that 
it  contains  the  remains  of  delicate  animals  not  often  found  as 
fossils. 

While  the  fauna  of  the  Lower  Cambrian  undoubtedly  lived  in 
water  of  very  considerable  depth,  it  was  not  oceanic  but  conti- 
nental, for  we  are  told  by  Walcott  that  "  one  of  the  most  impor- 
tant conclusions  is  that  the  fauna  of  the  Lower  Cambrian  lived 
on  the  eastern  and  western  shores  of  a  continent  that  in  its  gen- 
eral configuration  outlines  the  American  continent  of  to-day." 
"  Strictly  speaking,  the  fauna  did  not  live  upon  the  outer  shore 
facing  the  ocean,  but  on  the  shores  of  interior  seas,  straits,  or  la- 
goons that  occupied  the  intervals  between  the  several  ridges  that 
ran  from  the  central  platform  east  and  west  of  the  main  conti- 
nental land  surface  of  the  time." 

This  fauna  was  rich  and  varied,  but  it  was  not  self-supporting, 
for  no  fossil  plants  are  found,  and  the  primary  food  supply  was 
pelagic.  Animals  adapted  for  a  rapacious  life,  such  as  the  ptero- 
pods,  were  abundant,  and  prove  the  existence  of  a  rich  supply  of 
pelagic  animals.  All  the  forms  known  from  the  fossils  are  either 
carnivorous,  like  the  medusae,  corals,  Crustacea,  and  trilobites,  or 
they  are  adapted,  like  the  sponges,  brachiopods,  and  lamellibranchs, 
for  straining  minute  organisms  out  of  the  water  or  for  gathering 
those  which  rained  down  from  above,  and  the  conditions  under 
which  they  lived  were  very  similar  to  those  on  the  bottom  at  the 
present  day. 

Walcott's  studies  show  that  the  earliest  known  fauna  had  the 
following  characteristics :  It  consisted,  so  far  as  the  record  shows, 
of  animals  alone,  and  these  were  dependent  upon  the  pelagic  food 
supply  for  support.     While  small  in  comparison  with  manv  modern 


NATURAL  SELECTION,   AND    THE  ANTIQUITY  OF  LIFE     237 

animals,  they  were  gigantic  compared  with  primitive  pelagic  ani- 
mals. The  species  were  few,  but  they  represent  a  very  wide  range 
of  types.  All  these  types  have  modern  representatives,  and  most  of 
the  modern  types  are  represented  in  the  Lower  Cambrian.  Their 
home  was  not  the  bottom  of  the  deep  ocean,  but  the  shores  of  a 
continent  under  water  of  a  considerable  depth. 

The  Cambrian  fauna  is  usually  regarded  as  a  halfway  station 
in  a  series  of  animal  forms  which  stretches  backward  into  the 
past  for  an  immeasurable  period,  and  it  is  even  stated  that  the 
history  of  life  before  the  Cambrian  is  longer  by  many  fold  than 
its  history  since.  So  far  as  this  opinion  rests  on  the  diversity  of 
types  in  Cambrian  times,  it  has  no  good  basis  ;  for  if  the  views 
here  advocated  are  correct,  the  evolution  of  the  ancestral  stems 
took  place  at  the  surface,  and  all  the  conditions  necessary  for 
the  rapid  production  of  types  were  present  when  the  bottom 
fauna  first  became  established. 

As  we  pass  backward  toward  the  Lower  Cambrian  we  find 
closer  and  closer  agreement  with  the  zoological  conception  of  the 
character  of  primitive  life  on  the  bottom.  While  we  cannot  regard 
the  oldest  fauna  which  has  been  discovered  as  the  first  which 
existed  on  the  bottom,  we  may  feel  confident  that  the  first  fauna 
of  the  bottom  resembled  that  of  the  Lower  Cambrian  in  its  physi- 
cal conditions  and  in  its  most  distinctive  peculiarities,  —  the  abun- 
dance of  types,  and  the  slight  amount  of  differentiation  among  the 
representatives  of  these  types, —  and  we  must  regard  it  as  a  decided 
and  unmistakable  approximation  to  the  beginning  of  the  modern 
fauna  of  the  earth,  as  distinguished  from  the  more  ancient  and 
simple  fauna  of  the  open  ocean. 


LECTURE    X 

NATURAL   SELECTION    AND    NATURAL   THEOLOGY 


LECTURE   X 

NATURAL   SELECTION  AND   NATURAL  THEOLOGY 

DA-Rwin's  book  on  the  "  Origin  of  Species "  did  not  make  its 
way,  even  among  men  of  science,  without  searching  examination ; 
and  it  is  interesting  to  note  that,  in  the  early  days  of  its  history, 
all  of  its  most  prominent  advocates  were  English  in  their  intellec- 
tual training,  although  some,  like  Asa  Gray,  were  not  English  bv 
birth.  Tyell,  Wallace,  Darwin,  Gray,  and  Huxley  knew  Lamarck's 
writings  well,  and,  in  this  day  of  Neo-Lamarckism,  we  may  find 
profit  in  studying  the  influences  that  led  all  these  vigorous  and 
independent  thinkers  to  condemn  his  speculations  as  worse  than 
worthless^  while  they  welcomed  natural  selection  as  one  of  the 
greatest  triumphs  of  the  human  mind. 

The  story  of  the  reception  of  the  "  Origin,"  as  it  is  told  in 
Darwin's  letters,  shows  how  it  won  its  way  in  spite  of  prejudice. 
Belief  that  the  problem  is  one  that  man  may  hope  to  solve  was  rap- 
idly growing  among  the  thoughtful ;  for  a  long  series  of  brilliant 
discoveries  in  embryology,  in  anatomy,  in  paleontology,  in  geograph- 
ical biology,  and  in  many  other  fields,  had  shown  that  zoology  is 
orderly,  and  exhibits  laws,  like  other  sciences ;  but  the  remains 
of  so  many  failures  lay  beside  the  path  of  history  that  most  cau- 
tious students,  in  England  at  least,  were  in  a  hostile  rather  than  a 
sympathetic  frame  of  mind,  and  were  indisposed  to  welcome  a 
new  attempt  to  bring  all  these  classes  of  phenomena  into  a  single 
point  of  view. 

To  men  like  Huxley,  who  had  refused  to  have  anything  to 
say  to  a  necessary  principle  of  universal  progress,  and  had  grown 
weary  of  speculation,  Darwin's  book  commended  itself  as  strictly 
scientific ,  for  it  is  based  upon  the  hard  work  of  half  a  lifetime, 
and,  making  no  attempt  to  account  for  the  fundamental  properties 
R  241 


242  THE  FOUNDATIONS   OF  ZOOLOGY 

of  living  things,  which  it  takes  as  it  finds  them,  it  demonstrates 
that  the  features  in  which  the  species  of  living  things  differ  from 
one  another,  are  due  to  influences  that  are  still  at  work,  and  open 
to  observation  and  experiment  by  scientific  methods. 

Darwin  shows  that  individual  animals  and  plants,  even  those 
of  the  same  species,  differ  greatly  among  themselves ;  that  these 
differences  may  be  exhibited  by  any  characteristic  whatever  — 
those  upon  which  the  species  and  genera  of  the  systematist  are 
based,  as  well  as  those  which  had  been  held  to  be  varietal  or 
individual ;  that,  notwithstanding  these  differences,  offspring  tend 
to  resemble  their  parents,  and  to  be  like  them  in  the  main  ;  that 
man  is  able  to  bring  about,  and  to  fix  or  establish,  changes  of 
type,  by  breeding  from  selected  parents;  and  that  features  exactly 
like  those  upon  which  species  are  based  may  be  modified  or  pro- 
duced by  selection  ;  and  that  what  is  thus  accomplished  by  man 
may  come  about  with  equal  certainty,  even  if  more  slowly,  in 
nature  through  the  struggle  for  existence  and  the  extermination 
of  the  unsuccessful. 

None  of  these  propositions  are  very  profound,  or  very  difficult 
to  grasp.  They  call  for  no  unexampled  powers  of  abstract  thought, 
for  they  lie  so  near  the  surface  that  they  have  been  formulated 
again  and  again. 

Darwin  says :  "  My  brother,  who  is  a  very  sagacious  man, 
always  said,  *  You  will  find  that  some  one  has  been  before  you  ' ; " 
and  on  the  first  page  of  the  first  edition  of  the  "  Origin,"  which 
was  published  in  November,  1859,  he  says,  after  telling  the  reader 
that  the  subject  has  occupied  him  steadily  for  twenty  years :  "  My 
work  is  now  (1859)  nearly  finished;  but  as  it  will  take  me  many 
more  years  to  complete  it,  and  as  my  health  is  far  from  strong, 
I  have  been  urged  to  publish  this  Abstract.  I  have  the  more 
especially  been  induced  to  do  this,  as  Mr.  Wallace,  who  is  now 
studying  the  natural  history  of  the  Malay  archipelago,  has  arrived 
at  almost  exactly  the  same  general  conclusions  that  I  have  on 
the  origin  of  species.  In  1858  he  sent  me  a  memoir  on  this 
subject,  with  a  request  that  I  would  forward  it  to  Sir  Charles 
Lyell,  who  sent  it  to  the  Linnean  Society,  and  it  is  published 
in  the  third  volume  of  the  Journal  of  that  Society.  Sir  Charles 
Lyell  and   Dr.   Hooker,   who  both  knew  of  my  work,  —  the  latter 


NATURAL  SELECTION  AND  NATURAL   THEOLOGY        243 

having  read  my  sketch  of  •  1844,  —  honored  me  by  thinking  it 
advisable  to  publish,  with  Mr.  Wallace's  excellent  memoir,  some 
brief  extracts  from  my  manuscript." 

Soon  after  the  publication  of  the  "Origin,"  he  writes  to  Lyell 
as  follows :  "  Now  for  a  curious  thing  about  my  book,  and  then 
I  have  done.  In  last  Saturday's  Gardeners  Chronicle  a  Mr.  Patrick 
Mathew  publishes  a  long  extract  from  his  work  on  'Naval  Tim- 
ber and  Arboriculture,'  published  in  1831,  in  which  he  briefly 
but  completely  anticipates  the  theory  of  Natural  Selection."  A 
few  days  later,  in  the  Gardeners  CJironicle,  he  says  :  "  I  freely 
acknowledge  that  Mr.  Mathew  has  anticipated  by  many  years  the 
explanation  which  I  have  offered  of  the  origin  of  species,  under 
the  name  of  natural  selection.  I  can  do  no  more  than  offer  an 
apology  to  Mr.  Mathew  for  my  entire  ignorance  of  this  publica- 
tion. If  another  edition  of  my  work  is  called  for,  I  will  insert 
to  the  foregoing  effect." 

A  few  years  later  Darwin  writes  to  Hooker  as  follows :  "  Talk- 
ing of  the  'Origin,'  a  Yankee  has  called  my  attention  to  a  paper 
attached  to  Dr.  Wells's  famous  '  Essay  on  Dew,'  which  was  read 
in  1813  to  the  Royal  Society,  but  not  then  printed,  in  which  he 
applies  the  principle  of  Natural  Selection  to  the  Races  of  Man, 
So  poor  old  Patrick  Mathew  is  not  the  first,  and  he  cannot,  or 
ought  not,  any  longer  to  put  on  his  title-page  '  Discoverer  of 
the  Principle  of  Natural  Selection.'  " 

In  the  "  Historical  Sketch  "  which  is  printed  in  all  subsequent 
editions,  Darwin  fulfils  his  promise  to  Mathew,  and  also  refers 
at  length  to  Dr.  W.  C.  Wells  of  Charleston,  S.C,  whose  state- 
ment is  contained  in  "An  Account  of  a  White  Female,  part  of 
whose  skin  resembles  that  of  a  negro,"  afterwards  (1818)  pub- 
lished as  part  of  an  appendix  to  his  "Two  Essays  on  Dew  and 
Single  Vision." 

After  remarking  that  negroes  and  mulattoes  enjoy  an  immunity 
from  certain  tropical  diseases,  he  observes  that  all  animals  tend 
to  vary  to  some  degree,  and  that  agriculturalists  improve  their 
domestic  animals  by  selection,  and  that  what  is  done  in  the  latter 
case  by  art,  seems  to  be  done  with  equal  efficacy,  though  more 
slowly,  by  nature,  in  the  formation  of  varieties  of  mankind,  fitted  for 
the  country  which  they  inhabit.     Of  the  accidental  varieties  of  man. 


244  THE  FOUNDATIONS   OF  ZOOLOGY 

which  would  occur  among  the  first  few  and  scattered  inhabitants 
of  the  middle  regions  of  Africa,  some  one  would  be  better  fitted 
than  the  others  to  bear  the  diseases  of  the  country.  This  race 
would  consequently  multiply,  while  the  others  would  decrease, 
not  only  from  their  inability  to  sustain  the  attacks  of  disease  but 
from  their  incapacity  to  contend  with  their  more  vigorous  neigh- 
bors. The  color  of  this  vigorous  race  would  be  black  for  the 
reason  given.  The  same  disposition  to  form  varieties  still  existing, 
a  darker  and  a  darker  race  would  in  course  of  time  occur ;  and 
as  the  darkest  would  be  the  best  fitted  for  the  climate,  this  would 
at  length  become  the  most  prevalent  if  not  the  only  race  in  the 
particular  country  in  which  it  had  originated. 

It  is  sometimes  said  that  the  success  of  the  "  Origin,"  and 
the  independent  enunciation  of  its  central  conception  by  so  many 
thinkers,  proved  that  the  subject  was  in  the  air,  or  that  men's 
minds  were  prepared  for  it;  but  Darwin  says  he  does  not  think 
this  was  strictly  true ;  for  while  he  occasionally  sounded  not  a  few 
naturalists,  he  never  happened  to  come  across  a  single  one  who 
seemed  to  doubt  about  the  permanency  of  species.  Even  Lyell 
and  Hooker,  though  they  would  listen  with  interest,  never  seemed 
to  agree.  He  says  that  he  tried  once  or  twice  to  explain  to  able 
men  what  he  meant  by  Natural  Selection,  but  signally  failed ; 
and  Huxley  bears  witness,  as  do  others,  that  the  sentiment  of 
the  most  profound  naturalists  was  critical  rather  than  sympathetic. 

Darwin  tells  us  the  publication  in  1858  of  Mr.  Wallace's 
clever  and  admirably  expressed  essay,  together  with  an  abstract 
from  his  own  notes,  "  excited  very  little  attention,  and  the  only 
published  notice  of  them  which  I  can  remember  was  by  Profes- 
sor Houghton  of  Dublin,  whose  verdict  was  that  all  that  was  new 
in  them  was  false,  and  that  what  was  true  was  old." 

Darwin  has  himself  tried  to  analyze  the  mental  qualities  and 
conditions  on  which  his  success  has  depended ;  and  he  is  no 
doubt  right  in  attributing  much  of  his  success  as  an  investigator 
and  much  of  his  influence  upon  scientific  thought  to  the  indefati- 
gable industry  which  is  so  clearly  shown  in  all  his  works ;  and 
the  success  of  the  "  Origin "  was  no  doubt  due  to  its  vast  array 
of  demonstrated  facts,  rather  than  to  the  way  in  which  the  argu- 
ment   was    stated ;    but    Lamarck    was    also    an    earnest,    simple- 


NATURAL  SELECTION-  AND   NATURAL    THEOLOGY        245 

hearted,  indefatigable  student,  whose  interest  in  nature  never 
halted  or  wavered,  and  whose  most  important  work,  the  "  History 
of  the  Invertebrates,"  was  undertaken  when  he  was  old  and  blind, 
and  in  poverty  and  suffering. 

We  must,  therefore,  search  more  deeply  for  the  secret  of  the 
rejection  by  English  naturalists  of  Lamarck's  hypothesis,  and  their 
welcome  to  the  "  Origin  of  Species." 

In  1844,  or  sixteen  years  before  the  publication  of  the  "Ori- 
gin," Darwin  writes  to  Hooker:  "I  have  been  now  ever  since 
my  return  engaged  in  a  very  presumptuous  work,  and  I  know 
not  one  individual  who  would  not  say  a  very  foolish  one.  I  am 
so  struck  with  the  distribution  of  the  Galapagos  organisms,  etc., 
and  with  the  character  of  the  American  mammifers,  etc.,  that  I 
determined  to  collect  blindly  every  sort  of  fact  which  could  bear 
in  any  way  on  what  are  called  species.  I  have  read  heaps  of 
agricultural  and  horticultural  books  and  have  never  ceased  collect- 
ing facts.  At  last  gleams  of  light  have  come,  and  I  am  almost 
convinced  (quite  contrary  to  the  opinion  I  started  with)  that  spe- 
cies are  not  (it  is  like  confessing  a  murder)  immutable.  Heaven 
forfend  me  from  Lamarck  nonsense  of  a  '  tendency  to  progres- 
sion,' '  adaptations  through  the  slow  willing  of  animals,'  etc.  But 
the  conclusions  I  am  led  to  are  not  widely  different  from  his: 
though  the  means  of  change  are  wholly  so.  /  think  I  Jiave  found 
out  (here's  presumption)  the  simple  tvay  in  zvhich  species  become 
exquisitely  adapted  to  various  ends.  You  will  now  groan,  and  think 
to  yourself,  'on  what  a  man  I  have  been  wasting  my  time  and 
writing  to.'     I  should  five  years  ago  have  thought  so." 

Darwin  gives  a  list  of  thirty-five  writers  who,  during  the  early 
part  of  the  nineteenth  century,  expressed  belief  in  the  mutability  of 
species,  or,  at  least,  disbelief  in  separate  acts  of  creation,  before  his 
own  work  was  published ;  and  even  at  an  earlier  date  the  specula- 
tions of  Oken,  Goethe,  Buffon,  and  others  had  brought  the  subject 
into  prominence. 

Of  all  these  writers  Lamarck  had  put  the  question  in  the  most 
definite  form  and  discussed  it  most  completely.  His  views  are  the 
only  ones  which  had  attracted  much  attention,  but  while  they  were 
well  known  in  England  they  had  little  influence  there  upon  the  men 
of  science,  except  to  cast  discredit  on  new  attempts.     "  The  hypoth- 


246  THE  FOUNDATIONS  OF  ZOOLOGY 

esis  had  been  sadly  damaged  by  its  supporters,"  says  Huxley,  who 
"  had  studied  Lamarck  attentively,"  but  had  found  no  ground  for 
changing  his  negative  and  critical  attitude. 

In  1849  Darwin  said  of  Lamarck,  "his  absurd  though  clever 
work  has  done  the  subject  harm  "  ;  and  I  have  quoted  (p.  82)  ex- 
tracts from  works  written  about  the  time  the  "Origin  "  was  published, 
by  naturalists  who  saw  clearly  that  nurture  can  have  no  practical 
share  in  the  origin  of  species  unless  it  has  a  determinate  influence  in 
beneficial  lines ;  nor  are  matters  helped  at  all  by  attributing  this 
determinate  beneficial  influence  to  a  necessary  law  of  universal  prog- 
ress ;  for  natural  laws  are  not  rulers  or  governors  over  nature,  but 
generalizations  from  an  experience  which  seems  to  teach,  among 
other  things,  that  progress  is  neither  necessary  nor  universal. 

"  If  all  organic  beings  thus  tend  to  rise  in  the  scale,  how  is  it  that 
throughout  the  world  a  multitude  of  the  lowest  forms  still  exist ;  and 
how  is  it  that  in  each  great  class  some  forms  are  far  more  highly 
developed  than  others .''  Why  have  not  the  more  highly  devel- 
oped forms  everywhere  supplanted  and  exterminated  the  lower } 
Lamarck,  who  believed  in  an  innate  and  inevitable  tendency  towards 
perfection  in  all  organic  beings,  seems  to  have  felt  this  difificulty  so 
strongly,  that  he  was  led  to  suppose  that  new  and  simple  forms  are 
continually  being  produced  by  spontaneous  generation.  Science  has 
not  yet  proved  the  truth  of  this  belief,  whatever  the  future  may 
reveal.  On  my  theory  the  continued  existence  of  lowly  organisms 
offers  no  difificulty ;  for  natural  selection,  or  the  survival  of  the 
fittest,  does  not  necessarily  include  progressive  development,  —  it 
only  takes  advantage  of  such  variations  as  arise  and  are  beneficial  to 
each  creature  under  its  complex  relations  of  life."  ^ 

Even  if  it  were  shown  that  the  sum  of  the  conditions  that  make 
up  the  environment  of  organisms  does,  in  the  long  run,  make  for 
fitness,  the  problem  of  the  naturalist  is  not  the  existence  of  adapta- 
tions as  such,  but  the  existence  of  adaptive  species ;  and  if  the 
fitness  of  the  living  world  as  a  whole  were  to  be  explained  by  a 
general  law  of  evolution,  this  would  not  tell  us  why  we  do  not  find 
innumerable  transitional  forms,  living  side  by  side  with  the  actual 
species,   and   filling  all  the  gaps  between  them. 

While  events  in  general  take  place,  no  doubt,  according  to  the 

1  "  Origin,"  p.  98. 


NATURAL  SELECTION  AND   NATURAL    THEOLOGY         247 

mathematical  law  of  probability,  and  exhibit  statistical  types,  there 
is  no  necessary  or  inherent  parallelism  between  the  "  generic  types  " 
of  the  physical  world  and  those  which  are  known  to  naturalists  as 
species;  for  we  find  mollusks  and  Crustacea  and  fishes  living  side  by 
side  in  every  little  brook,  the  world  over ;  and  every  part  of  the  land 
and  of  the  water,  in  all  regions  of  the  earth,  has  its  own  representatives 
of  most  of  the  great  groups  of  animals  and  plants.  Agassiz's  "Essay 
on  Classification"  failed  to  deal  that  death  blow  to  the  "Origin," 
which  was  in  the  mind  of  the  author,  although  Lamarckians  might 
still  study,  with  profit,  its  clear,  earnest,  and  impregnable  demonstra- 
tion that  there  is  no  parallelism  between  the  generic  types  of  the 
physical  environment  of  each  species  and  the  attributes  of  the 
species  itself. 

The  most  notable  peculiarity  of  the  English  attitude  of  mind 
regarding  the  species  question  was  the  feeling  so  clearly  expressed 
by  Darwin,  by  Huxley,  and  by  many  other  naturalists,  that  the 
attempts  at  a  solution  had  so  far  been  valueless,  and  that  they 
had  even  excited  hostility.  Another  notable  fact  is  that,  while  the 
thirty-five  authors,  between  1800  and  i860,  to  whom  Darwin  refers, 
wrote  in  many  countries,  in  England,  Ireland,  Scotland,  the  United 
States,  France,  Belgium,  Germany,  and  Russia,  the  four  who  defi- 
nitely recognized  and  clearly  stated  the  law  of  natural  selection, 
Wells,  Mathew,  Wallace,  and  Darwin,  were  English  in  their 
intellectual  training. 

In  order  to  grasp  the  full  significance  of  the  influences  which 
led  to  the  production  and  acceptance  of  the  "Origin,"  it  is  clear  that 
we  must  try  to  understand  what  caused  a  hostile  frame  of  mind 
towards  Lamarck,  while  there  was  no  permanent  hostility  to  the 
"  Origin." 

There  seems  to  me  to  be  no  doubt  that  this  influence  came,  in 
part  at  least,  from  the  works  of  a  school  of  writers  on  what  was 
called  natural  theology,  among  whom  John  Ray  (1624-1705),  Wil- 
liam Derham  (1657-1735),  and  William  Paley  (1743- 1805)  are  best 
known.  None  of  these  men  was  a  notable  contributor  to  science  : 
even  Ray,  who  has  the  greatest  claim  to  remembrance  as  a  natu- 
ralist, was  by  no  means  the  equal  of  contemporary  students  of 
science  ;  and  Derham  did  nothing  in  science  except  to  edit  Ray's 
works ;    while    Paley  makes    no    claim    to  originality,  owing   much, 


248  THE  FOUNDATIONS   OF  ZOOLOGY 

both  facts  and  the  manner  of  presenting  them,  to  the  Dutch 
writer,  Nieuwentyt,  who,  in  1716,  wrote  a  book  which  was  trans- 
lated into  English  (1730)  under  the  title  of  "The  Religious 
Philosopher,"  although  the  real  starting-point  for  the  series  of 
English  books  on  natural  theology,  which  culminated  in  the  Bridge- 
water  Treatises  about  1836,  was  the  work  on  "The  Wisdom  of  God 
Manifested  in  the  Works  of  Creation,"  by  Ray  (1691),  who  illus- 
trates the  delicacy  and  usefulness  of  all  the  parts  of  living  creat- 
ures by  such  familiar  examples  of  adaptation  as  the  structure  of 
the  eye,  the  hollowness  of  the  bones,  the  stomach  of  the  camel, 
the  armor  of  the  hedgehog,  etc. 

Science  formed  no  part  of  a  "liberal"  education  in  the  early 
days  of  our  century,  and  the  youth  who  was  born  with  the  instincts 
of  a  naturalist  found  little  to  satisfy  these  instincts  except  books 
of  this  sort,  which,  scanty  and  inadequate  as  they  are,  have  the 
charm,  which  often  eludes  the  laboratory  handbook,  of  emphasiz- 
ing the  environment  as  the  complement  of  structure.  The  share 
of  the  writers  on  natural  theology  in  shaping  the  education  of 
English  naturalists  has  not  been  adequately  esteemed ;  for  they 
substituted,  for  the  vulgar  ignorance  which  finds  nothing  but  dis- 
gust spiced  with  immodesty  in  our  bodily  frame,  a  living  sense  of 
the  grandeur  and  instructiveness  of  animated  nature.  No  one  can 
read  Paley  and  fail  to  see  that  the  mechanism  of  living  things  is 
at  least  as  well  worthy  of  study  as  the  "  humanities " ;  for  what- 
ever our  opinion  of  the  value  of  his  conclusions  may  be,  he  shows 
that  there  is  a  field  for  the  profitable  employment  of  the  best 
powers  of  the  best  minds  in  the  most  familiar  plant ;  and  that 
the  humblest  worm  may  furnish  inexhaustible  delight,  and  may 
lead  us  to  questions  which  demand  the  utmost  exercise  of  our 
highest  faculties. 

In  1859  Darwin  writes  to  Lubbock:  "I  do  not  think  I  hardly 
ever  admired  a  book  more  than  Paley's  '  Natural  Theology.'  I 
could  almost,  formerly,  have  said  it  by  heart";  and  in  his  autobi- 
ography he  says  the  logic  of  Paley's  "  Evidences  "  and  of  his  "  Nat- 
ural Theology"  "gave  me  as  much  delight  as  did  Euclid.  The 
careful  study  of  these  works,  without  attempting  to  learn  any  part 
by  rote,  was  the  only  part  of  the  academic  course  which,  as  I 
then  felt,  and  as   I  still  believe,  was  of  the  least  use  to  me  in  the 


NATURAL   SELECTION  AND  NATURAL    THEOLOGY         249 

education  of  my  mind.  I  did  not  at  that  time  trouble  myself  about 
Paley's  premises ;  and,  taking  these  on  trust,  I  was  charmed  and 
convinced  by  the  long  line  of  argumentation." 

As  most  of  the  writers  on  natural  theology  were  clergymen 
who  united  thorough  literary  education  with  professional  training 
in  the  art  of  interesting  untrained  audiences,  they  made  use  of 
simple,  familiar  illustrations ;  and  Paley,  whose  influence  was  great- 
est, bases  his  argument  upon  such  things  as  the  fitness  of  the  eye 
for  vision ;  the  adaptation  of  the  joints  of  our  limbs  to  the  move- 
ments which  the  limbs  are  fitted  for  making ;  the  fitness  of  feathers 
for  covering  animals  which  fly;  the  advantage  of  symmetry  in 
paired  organs,  like  limbs  and  eyes;  the  compact  arrangement  of 
parts  exhibited  by  the  irregular  viscera  which  are  packed  within 
the  body  without  disturbing  its  external  symmetry ;  and  similar 
facts  which  may  be  easily  verified  by  all :  but  early  in  our  century 
there  was  published  in  England  a  series  of  books  which,  approach- 
ing natural  science  in  the  same  way,  appeal  to  more  mature  minds. 
The  Rev,  Francis  Henry,  eighth  Earl  of  Bridge  water,  who  died 
Feb.  II,  1829,  left  by  will  to  the  Royal  Society  ^8000,  to  be  paid 
to  the  author  or  authors  selected  to  write  and  publish  a  treatise 
"  On  the  Power,  Wisdom,  and  Goodness  of  God  as  manifested  in 
Creation."  The  president  of  the  society  selected  eight  persons, 
each  to  undertake  a  branch  of  the  subject  and  each  to  receive 
;;^iooo,  together  with  any  benefit  which  might  accrue  from  the  sale 
of  his  work. 

The  aim  of  these  treatises  is  sufficiently  indicated  by  the  general 
title  which  was  given  to  them  in  the  will ;  but  this  is  set  forth, 
more  at  length,  in  the  one  on  "  Geology  and  Mineralogy  considered 
with  Reference  to  Natural  Theology,"  by  the  Rev.  William  Buckland 
(1836). 

"Its  purpose,"  he  tells  us,  "is  to  extend  into  the  organic  remains 
of  a  former  world  the  same  kind  of  investigation  which  Paley  had 
pursued  with  so  much  success,  in  his  examination  of  the  evidences 
of  design  in  the  mechanical  structure  of  the  corporeal  frame  of 
man,  and  of  the  inferior  animals  which  are  placed  with  him  on 
the  present  surface  of  the  earth. 

"  Every  comparative  anatomist  is  familiar,"  he  says,  "  with  the 
beautiful  examples  of  mechanical   contrivances  and   compensations 


250  THE  FOUNDATIONS   OF  ZOOLOGY 

which  adapt  each  existing  species  of  herbivora  and  carnivora 
to  its  own  position,  place,  and  state  of  Hfe.  Such  contrivances 
began  not  with  living  species ;  the  geologist  demonstrates  their 
prior  existence  in  the  extinct  forms  of  the  same  genera,  which  he 
discovers  beneath  the  surface  of  the  earth,  and  he  claims  for  the 
author  of  these  fossil  forms  under  which  the  first  types  of  such 
mechanism  were  embodied,  the  same  high  attributes  of  Wisdom 
and  Goodness,  the  demonstration  of  which  exalts  and  sanctifies  the 
labors  of  Science  in  her  investigations  of  the  living  world. 

"The  myriads  of  petrified  remains  which  are  disclosed  by  the 
researches  of  geology  all  tend  to  prove  that  our  planet  has  been 
occupied  in  times  preceding  the  creation  of  the  human  race  by 
extinct  species  of  animals  and  vegetables  made  up,  like  living 
organic  bodies,  of  clusters  of  contrivances."  It  is  the  description 
of  these  "  contrivances  "  which  has  given  to  this  work  and  others 
like  it  their  educational  influence. 

While  all  the  books  of  this  sort  take  special  creation  for  granted, 
and  are  based,  in  one  way  or  another,  upon  the  assumption  that 
fitness  involves  and  implies  "contrivance,"  they  did  good  service 
to  science  by  keeping  clearly  and  distinctly  before  the  minds  of 
English  naturalists  the  fact  that,  whatever  the  reason  may  be, 
adaptation  or  adjustment  is  the  essential  characteristic  of  living 
beings;  that  life  is  adjustment;  and  that  what  Aristotle  sought  to 
define  as  the  "essence"  of  a  living  being,  is  its  fitness  for  its  place 
in  nature. 

As  the  facts  of  embryology  and  paleontology  and  geography 
began  to  press  for  explanation,  and  it  became  more  and  more 
obvious,  during  the  first  part  of  the  nineteenth  century,  that  species 
must  owe  their  origin  to  some  influence  which  is  part  of  the  dis- 
coverable order  of  nature,  it  is  due  to  the  writers  on  natural  theology 
that  the  English  naturalists  repudiated  all  inadequate  attempts, 
like  that  of  Lamarck,  and,  maintaining  a  sturdy  suspense,  waited 
for  some  more  adequate  explanation. 

Huxley  says  that  in  conversation  with  Herbert  Spencer  in  1852 
and  the  years  following,  he  himself  took  the  ground  that  no  sug- 
gestion respecting  the  causes  of  the  transmutation  assumed,  which 
had  been  made,  was  in  any  way  adequate  to  explain  the  phenomena ; 
and  Darwin's  "Letters"  show  that  his  point  of  view  was  at  first 


NATURAL  SELECTION  AMD   NATURAL    THEOLOGY         2$  I 

identical  with  that  of  Huxley,  who  says  that  the  same  influence 
which  led  him  to  put  as  little  faith  in  the  current  speculations  on 
this  subject  as  in  the  venerable  traditions  recorded  in  the  first 
two  chapters  of  Genesis,  was  perhaps  by  a  curious  irony  of  fate 
more  potent  than  any  other  in  keeping  alive  a  sort  of  pious  con- 
viction that  the  transmutation  of  species,  after  all,  would  turn  out 
true. 

He  says,  too,  that  most  of  his  contemporaries  who  thought 
seriously  about  the  matter  were  very  much  in  his  own  state  of 
mind,  inclined  to  say  to  both  creationists  and  evolutionists,  "  A  plague 
on  both  your  houses !  "  and  disposed  to  turn  aside  from  an  intermi- 
nable and  fruitless  discussion  to  labor  in  the  fertile  fields  of  ascer- 
tainable fact. 

The  publication  of  the  work  of  Darwin  and  Wallace  had,  he 
tells  us,  the  effect  of  "  a  flash  of  light,  which  to  a  man  who  has 
lost  himself  in  a  dark  night,  suddenly  reveals  a  road  which,  whether 
it  takes  him  straight  home  or  not,  certainly  goes  his  way." 

"That  which  we  were  looking  for  and  could  not  find,  was  a 
hypothesis  respecting  the  origin  of  known  organic  forms,  which 
assumed  the  operation  of  no  causes  but  such  as  could  be  proved 
to  be  actually  at  work." 

The  "  Origin  "  provided  us  with  the  working  hypothesis  we 
sought.  .  .  .  My  reflection,  when  I  first  made  myself  master  of 
the  central  idea  .  .  .  was,  How  extremely  stupid  not  to  have 
thought  of  that !  .  .  .  the  facts  of  variability,  of  the  struggle 
for  existence,  of  adaptation  to  conditions,  were  notorious  enough  ; 
but  none  of  us  had  suspected  that  the  road  to  the  heart  of  the 
species  problem  lay  through  them,  until  Darwin  and  Wallace 
dispelled  the  darkness,  and  the  beacon-fire  of  the  '  Origin  '  guided 
the  benighted." 

Clear  and  strong  as  was  the  light  which  fell  on  natural  history 
with  the  discovery  of  the  full  significance  of  the  fierce  and  un- 
ceasing struggle  for  existence  which  springs  from  the  geometrical 
multiplication  of  organisms,  the  "beacon-fire  of  the  'Origin'" 
shone  with  no  less  penetration  on  the  basis  of  the  argument  of 
Ray  and  Paley  and  the  authors  of  the  Bridgcwater  Treatises ;  for 
it  revealed  the  unbroken  chain  of  natural  causation  which  binds 
up,   with   the  adaptations  which    Paley    makes    use  of,    those   that 


252  THE  FOUNDATIONS  OF  ZOOLOGY 

are  pointed  out  by  Buckland,  so  that  it  is  no  longer  possible  to 
regard  them  as  independent  and  distinct  contrivances. 

Darwin  says :  "  The  old  argument  from  design  in  nature,  as 
given  by  Paley,  which  formerly  seemed  to  me  so  conclusive,  fails 
now  that  natural  selection  is  discovered.  We  can  no  longer  argue 
that,  for  instance,  the  beautiful  hinge  of  a  bivalve  shell  must 
have  been  made  by  an  intelligent  being.  There  seems  to  be  no 
more  design  in  the  variability  of  organic  beings  and  in  the  action 
of  natural  selection  than  in  the   course  which  the  wind  blows." 

If  the  supposed  analogy  between  human  contrivances  and  the 
works  of  nature  be  a  mistake,  Paley  assuredly  makes  this  mistake; 
although  this  is  not  pointed  out  in  any  hostile  spirit,  but  solely 
for  the  purpose  of  showing  those  who  are  convinced,  with  Darwin, 
of  the  failure  of  the  "  old  argument  from  design  as  given  by 
Paley,"  that  they  may  perhaps  find  a  stronger  argument ;  and 
that  there  may  be  more  wisdom  in  Huxley's  assertion  that  it  is 
only  "  the  commoner  and  coarser  forms  of  teleology "  that  fail 
when  tested  by  natural  selection. 

It  is  obvious  to  all  that  with  the  discovery  of  the  significance 
of  natural  selection,  the  teleology  which  supposes  that  the  eye,  such 
as  we  see  it  in  man  or  one  of  the  higher  vertebrates,  was  made 
with  the  precise  structure  which  it  exhibits,  for  the  purpose  of 
enabling  the  animal  which  possesses  it  to  see,  has  undoubtedly 
received  its  death-blow ;  although  Huxley,  while  pointing  this  out, 
reminds  us  that  "  nevertheless  it  is  necessary  to  remember  that 
there  is  a  wider  teleology,  which  is  not  touched  by  the  doctrine 
of  Evolution,  but  is  actually  based  upon  the  fundamental  proposi- 
tion of   Evolution." 

Asa  Gray,  writing  at  the  same  or  nearly  the  same  time,  soon 
after  the  "Origin"  was  published,  says  he  cannot  perceive  that  Dar- 
win brings  in  any  new  kind  of  difficulty,  and  he  expresses  his 
conviction  that  they  who  think  there  is  any  incompatibility  be- 
tween belief  in  the  mutability  of  species  and  belief  in  teleology 
occupy  a  position  which  is  not  only  untenable,  but  "  highly  unwise 
and  dangerous  in  the  present  state  and  present  prospects  of  physi- 
cal and  physiological  science."  "We  should,"  he  says,  "expect 
the  philosophical  atheist  to  take  this  ground ;  also,  until  better 
informed,    the    unlearned    and    unphilosophical     believer ;    but    we 


NATURAL  SELECTION  AND  NATURAL   THEOLOGY        253 

should  think  the  thoughtful  theistic  philosopher  would  take  the 
other  side.  Not  to  do  so  seems  to  concede  that  only  supernatural 
events  can  be  shown  to  be  designed,  which  no  theist  can  admit  — 
seems  also  to  misconceive  the  scope  and  meaning  of  all  ordinary 
arguments  from  design  in  nature." 

Where  can  we  find  three  more  eminent  naturalists,  or  three 
men  more  thoughtful,  or  more  distinguished,  than  Darwin,  Huxley, 
and  Gray,  for  integrity  of  mind  and  for  that  sturdy  conservatism 
which  is  not  incompatible  with  independence  .-* 

What  are  we  to  infer  if,  after  studying  a  subject  they  were  all 
so  preeminently  fitted  for  handling,  a  subject  which  falls  within  a 
province  to  which  all  three  had  devoted  their  lives,  they  are  led 
to  such  contradictory  conclusions  that  one  asserts  that  the  old 
argument  from  design  fails,  now  that  natural  selection  is  discov- 
ered, while  another  is  convinced  that  natural  selection  presents  to 
the  believer  in  teleology  no  new  difficulties,  at  the  same  time  that 
a  third  tells  us  that  although  natural  selection  has  given  a  death- 
blow to  the  commoner  and  coarser  forms  of  teleology,  there  is  a 
wider  teleology  which  it  does  not  touch  at  all .-' 

Is  it  not  clear  that  they  have  not  all  considered  the  same 
question }  Must  we  not  seek  a  meeting-point  for  Darwin  and 
Gray  in  Huxley's  more  profound  conception  of  the  matter }  May 
not  the  argument  from  design  which  Darwin  had  in  mind  be 
identical  with  the  commoner  and  coarser  teleology  of  Huxley } 
And  may  not  the  wider  teleology  which,  as  Huxley  tells  us,  is 
untouched  by  natural  selection,  be  that  in  which  Gray  finds  no 
new  difficulties } 

Before  we  try  to  find  out  what  this  wider  teleology  is,  it  may 
be  well  to  look  more  closely  into  the  nature  of  the  "  death-blow " 
which  science  has  given  to  "the  old  argument  for  design  as  given 
by  Paley,"  and  to  this  I  shall  devote  this  and  the  following 
lecture;  while  I  shall  try  to  show,  in  the  lecture  on  the  Mechan- 
ism of  Nature,  that  zoology  leaves  ample  room  for  a  wider  tele- 
ology, which  may  be  independent  of  research  into  the  sciences. 

This  blow  cannot  have  come  from  the  mere  extension,  as  such, 
of  the  domain  of  natural  causation;  for  Paley  was  as  familiar  as 
we  with  Newton's  demonstration  that  all  the  hosts  of  heaven  are 
a  vast  mechanism,  regulated  according  to  the  same  laws  as  those 


254  THE  FOUNDATIONS  OF  ZOOLOGY 

which  are  shown  by  a  falling  stone.  When  Paley's  argument 
seemed  so  conclusive  to  Darwin,  he  had  studied  Lyell ;  nor  did 
he  doubt  at  all  that  the  history  of  the  earth,  as  we  find  it 
recorded  in  the  rocks,  is  also  part  of  the  same  orderly  system  of 
nature,  and  the  changes  now  going  on  upon  its  surface  part  of 
the  same  orderly  history.  No  one  finds  any  death-blow  to  teleology 
in  our  confidence  that  the  future  history  of  the  earth,  and  of  the 
solar  system,  and  of  the  stellar  universe  will  be  an  orderly  extension 
of  its  past  history ;  and,  far  from  asking  whether  this  view  of 
astronomy  is  rational,  the  teleologist  asserts  that  an  impregnable 
basis  for  his  argument  must  be  sought  in  the  fact  that  it  is 
rational ;  for  if  instead  of  order  we  discovered  only  a  chaotic  or 
unintelligible  history,  which  afforded  no  ground  for  reasonable 
expectation  as  to  the  future,  it  is  hard  to  see  where  he  could 
find  any  basis  for  his  argument,  for  this  seems  to  be  founded  on 
our  confidence  in  the  order  of  nature. 

Paley  himself  points  out  that,  far  from  weakening  his  argu- 
ment, the  appearance  of  new  individual  organisms,  in  the  course 
of  nature,  by  birth,  is  its  very  strength ;  and  he  argues  that  if 
the  finder  of  a  watch  should  find  that  it  possessed  the  property 
of  producing,  in  the  course  of  its  movements,  other  watches  like 
itself,  and  so  on  indefinitely,  this  discovery  would  increase  his 
admiration  of  the  consummate  skill  of  the  contriver.  "  Though 
it  be  no  longer  probable  that  the  individual  watch  which  our 
observer  had  found  was  made  immediately  by  the  hand  of  an 
artificer,  yet  doth  not  the  alteration  in  any  wise  affect  the  inference 
that  an  artificer  hath  been  originally  employed  and  concerned  in 
the  production.  The  argument  from  design  and  contrivance 
remains  as  it  was.  Marks  of  design  and  contrivance  are  no 
more  accounted  for  now  than  they  were  before.  Our  going  back 
ever  so  far  brings  us  no  nearer  to  the  least  degree  of  satisfaction 
upon  the  subject." 

This  passage  shows  that  no  death-blow  can  have  been  given 
to  his  argument  by  anything  inherent  in  the  demonstration  of  the 
mutability  of  species,  in  itself ;  and  that  the  blow  must  have 
fallen  upon  some  preconception  of  the  matter ;  for  if  any  find 
evidence  of  contrivance  in  the  anatomical  structure  and  in  the 
functional   activity   of   the    human    heart,   for   example,   and   in    its 


NATURAL  SELECTION  AND  NATURAL    THEOLOGY         255 

development,  according  to  nature,  from  a  germ-cell  which  was  part 
of  the  body  of  a  preexisting  organism,  I  do  not  see  how  they  can 
find  anything  but  new  reason  for  their  opinion  in  the  discovery 
that  men  and  dogs  and  elephants  and  whales  have  all  inherited 
their  hearts  from  a  common  mammalian  ancestor ;  nor  need  the 
proof  furnished  by  the  structure  and  development  of  the  heart  in 
all  air-breathing  vertebrates,  of  still  more  remote  descent  from 
ancestors  that  lived  in  the  water  and  breathed  by  gills,  fail  to  give 
new  strength  to  the  opinion. 

Huxley,  in  1864,  says:  "If  we  apprehend  the  spirit  of  the 
'  Origin  of  Species '  rightly,  nothing  can  be  more  opposed  to  tele- 
ology as  it  is  commonly  understood  than  the  Darwinian  theory. 
According  to  teleology,  each  organism  is  like  a  rifle  bullet  fired 
straight  at  a  mark ;  according  to  Darwin,  organisms  are  like  grape- 
shot,  of  which  one  hits  something  and  the  rest  fall  wide. 

"  For  the  teleologist  an  organism  exists  because  it  was  made 
for  the  conditions  in  which  it  is  found ;  for  the  Darwinian  an 
organism  exists  because,  out  of  the  many  of  its  kind,  it  is  the 
only  one  which  has  been  able  to  persist  in  the  conditions  in  which 
it  is  found.  Teleology  implies  that  the  organs  of  every  organism 
are  perfect  and  cannot  be  improved ;  the  Darwinian  theory  simply 
affirms  that  they  work  well  enough  to  enable  the  organism  to 
hold  its  own  against  such  competitors  as  it  has  met  with,  but 
admits  the  possibility  of  indefinite  improvement.  But  an  example 
may  bring  into  clearer  light  the  profound  opposition  between  the 
ordinary  teleological  and  the  Darwinian  conception. 

"Cats  catch  mice,  small  birds,  and  the  like,  very  well.  Tele- 
ology tells  us  that  they  do  so  because  they  were  constructed  for 
so  doing, — that  they  are  perfect  mousing  apparatuses,  so  perfect 
and  so  delicately  adjusted  that  no  one  of  their  organs  could  be 
altered,  without  the  change  involving  the  alteration  of  all  the  rest. 
Darwinism  affirms,  on  the  contrary,  that  there  was  no  express  con- 
struction concerned  in  the  matter;  but  that  among  the  multitudi- 
nous variations  of  the  Feline  stock,  many  of  which  died  out  for 
want  of  power  to  resist  opposing  influences,  some,  the  cats,  were 
better  fitted  to  catch  mice  than  others,  whence  they  throve  and 
persisted,  in  proportion  to  the  advantage  over  their  fellows  thus 
offered  to  them. 


256  THE  FOUNDATIONS  OF  ZOOLOGY 

"  Far  from  imagining  that  cats  exist  in  order  to  catch  mice 
well,  Darwinism  supposes  that  cats  exist  because  they  catch  mice 
well,  —  mousing  being  not  the  end  but  the  condition  of  their 
existence." 

If  this  were  all  the  difficulty  natural  selection  puts  in  the  way 
of  the  argument  from  contrivance,  I  cannot  believe  Paley  would 
have  found  it  serious ;  for  it  is  obvious  that  "  it  is  not  necessary 
that  a  machine  be  perfect  in  order  to  show  with  what  design  it 
was  made";  and  I  imagine  Paley's  answer  to  Huxley  would  be 
that,  whether  the  cat  exists  for  catching  mice  or  because  of  catch- 
ing mice,  the  adjustment  between  its  mechanism  and  the  life  of 
mice  is  as  real  as  the  adjustment  between  the  movements  of  the 
watch  and  the  movements  of  the  earth,  and  as  useful  to  cats  as 
watches  are  to  those  who  make  and  buy  them ;  although  we  must 
not  forget  to  consider  cats  from  the  standpoint  of  the  mouse. 

Darwin's  objection  to  Paley's  argument  has  recently  been  de- 
veloped, at  greater  length,  by  Romanes,  who  holds  that  while  the 
origin  of  species  by  gradual  development  does  not  in  itself  affect 
the  argument  from  contrivance,  it  does  so,  when  contrasted  with 
belief  in  special  creation,  because  it  reveals  the  possibility  that 
structures  like  the  human  eye  may  have  been  proximately  due  to 
the  operation  of  physical  causes,  whereas  this  possibility  is  ex- 
cluded by  the  hypothesis  of  sudden  or  special  creation. 

If  the  eye,  as  we  find  it  in  man,  owes  its  origin  to  the  slow 
and  gradual  centralization  and  specialization,  by  natural  selection, 
of  a  vague  sensibility  to  light,  which  was  originally  diffused  over 
the  whole  surface  of  the  body,  it  follows  "that  each  step  in  the 
prolonged  and  gradual  development  of  the  eye  was  brought  about 
by  the  elimination  of  all  the  less  adapted  structures  in  any  given 
generation,  i.e.  the  selection  of  all  the  better  adapted  to  perpetuate 
the  improvement  by  heredity." 

"Will  the  teleologist,"  asks  Romanes,  "maintain  that  this  selec- 
tive process  is  itself  indicative  of  special  design }  If  so,  it  appears 
to  me,"  he  says,  "that  he  is  logically  bound  to  maintain  that  the 
little  veins  of  colored  sand,  and  of  fragments  of  shells  which  we 
so  often  find  on  the  seashore,  separated  out  from  the  acres  of 
yellow  sand  and  brought  together  by  the  selective  action  of  grav- 
ity,  are   all   equally  indicative   of    special    design."      "The   general 


NATURAL   SELECTION  AND  NATURAL    THEOLOGY        257 

laws  relating  to  specific  gravity  are  at  least  of  as  much  importance 
in  the  economy  of  nature  as  are  the  general  laws  relating  to  spe- 
cific differentiation  ;  and  in  each  illustration  alike  [that  is,  in  the 
eye  and  in  the  separation  and  segregation  of  the  sands  of  the 
sea-beach]  we  find  the  result  of  the  operation  of  known  physical 
causes  to  be  that  of  selection.  If  it  should  be  argued  in  reply 
that  the  selective  action  in  the  one  case  is  obviously  purposeless, 
while  in  the  other  it  is  as  obviously  purposive,  I  answer  that  this 
is  a  pure  assumption.  It  is,  perhaps,  not  too  much  to  say  that 
every  geological  formation  on  the  face  of  the  globe  is  either  wholly 
or  in  part  due  to  the  selective  influence  of  specific  gravity,  and 
who  can  say  that  the  construction  of  the  earth's  crust  is  a  less 
important  matter  in  the  general  scheme  of  things  (if  there  is  such 
a  scheme)  than  is  the  evolution  of  the  eye .-'  Or  who  shall  say 
that  because  we  see  an  apparently  intentional  adaptation  of  means 
to  ends  as  the  result  of  selection  in  the  case  of  the  eye,  there  is 
no  such  intention  served  by  the  result  of  selection  in  the  case  of 
the  seaweeds,  stones,  sand,  mud }  For  anything  that  we  know 
to  the  contrary,  the  supposed  intelligence  may  take  a  greater 
delight  in  the  latter  than  in  the  former  process." 

While  Romanes's  reasoning  is  identical  with  that  which  I  have 
already  quoted  from  Darwin,  its  failure  to  overthrow,  or  even 
to  fairly  meet,  Paley's  argument  is  made  all  the  more  clear  by 
Romanes's  more  explicit  statement  of  his  difficulty;  for  Paley's 
contention  is  not  that  the  eye  is  designed  in  any  way  which  may 
not  be  equally  true  of  nature  as  a  whole,  but  that  it  gives  peculiar 
evidence  of  design. 

However  we  may  have  come  by  our  eyes,  we  prize  sight  as 
a  most  useful  and  precious  endowment,  and  we  know  that  the 
adjustment  between  the  mechanism  of  the  eye  and  the  data  of 
optics  is  so  useful  to  all  who  see  that  they  may  at  any  time  owe 
to  it  their  lives ;  while  we  are  unable  to  attach  any  meaning  to  an 
assertion  that  the  course  which  the  wind  blows  is  useful  to  the 
wind,  whatever  may  be  the  unknown  significance  of  either  eye 
or  wind  in  the  economy  of  nature  as  a  whole. 

One  may  admit  total  ignorance  of  the  significance,  in  the  gen- 
eral scheme  of  nature,  of   the  skill  of  cats  in  catching  mice;    one 
may  fail  to  see  how  the  way  the  grains  of  sand  fall  can  be  useful 
s 


258  THE  FOUNDATIONS  OF  ZOOLOGY 

or  important  to  the  sand;  and  yet  see  clearly  that  skill  in  catching 
mice  is  useful  to  cats,  ^even  if  the  mouse  might  also  have  some- 
thing to  say  on  the  subject  if  he  could  be  heard. 

As  I  understand  "the  old  argument  from  design  as  given  by 
Paley,"  it  is  as  follows:  — 

(i)  Nothing  accounts  for  watches  but  mind. 

(2)  Nothing  accounts  for  living  things  unless  it  accounts  for 
watches. 

(3)  Nothing  but  mind  accounts  for  living  things. 

The  resemblance  between  the  watch  and  the  eye  is  no  less  real 
and  no  less  obvious  than  it  was  before  natural  selection  was  dis- 
covered ;  and  this  discovery  seems  to  me  so  far  from  destroying 
Paley's  minor  premise  that  it  gives  to  human  contrivances  a  sig- 
nificance of  which  Paley  never  dreamed ;  for  it  shows  that  the 
basis  for  his  argument,  which  he  finds  in  the  resemblance  between 
human  contrivances  and  the  attributes  of  living  things,  is  impreg- 
nable. 

If  it  be  true  that  natural  selection  has  given  a  death-blow  to 
his  argument,  Darwin  and  Huxley  and  Romanes  fail,  in  the  pas- 
sages I  have  quoted,  to  show  either  the  nature  of  the  blow  or 
how  it  hits  the  argument;  for  no  one  can  see  the  whole  meaning 
of  natural  selection  without  seeing  that  we  no  longer  have  any 
reason  to  think  that  the  history  of  watches  differs  in  any  funda- 
mental way  from  the  history  of  spiders'  webs,  and  birds'  nests, 
and  eyes,  and  cats. 

As  the  mind  refuses  to  believe  that  the  relation  between  cats 
and  mice  is  due  to  "  chance,"  the  difficulty  pre-Darwinian  thinkers 
found  in  accounting  for  it,  without  attributing  it  to  interference 
with  the  course  of  nature,  was  inability  to  find,  in  our  knowledge 
of  nature,  any  reason  why  the  life  of  mice  should  ever  be  brought, 
in  course  of  nature,  into  that  peculiar  relation  to  the  structure 
of  cats  which  we  call  physical  causation. 

Wallace  and  Darwin  have  shown  that  this  causal  relation 
actually  exists,  and  that  the  life  of  mice  is  an  important  element 
in  that  objective  or  physical  environment  of  cats  which  has  deter- 
mined all  that  is  distinctive  or  characteristic  in  their  structure  by 
extermination  and    survival.     While    it    may  be    no    explanation    of 


NATURAL   SELECTION  AND  NATURAL    THEOLOGY        259 

the  properties  which  cats  have  in  common  with  other  Uving  things, 
and  while  it  may  leave  the  hardship  which  cats  bring  to  mice  as 
much  of  a  puzzle  as  ever,  natural  selection  is  a  strictly  scientific 
explanation  of  the  point  in  question :  the  specific  adjustment  of 
cats  to  the  life  of  mice ;  for,  when  all  the  conditions  of  the  prob- 
lem are  known,  it  shows  that  we  have,  through  the  discoveries  of 
Darwin  and  Wallace,  the  same  rational  confidence  that  the  life  of 
mice  will  modify  the  structure  of  cats  as  we  have  for  judicious 
expectation  that  a  current  in  the  ocean  will  modify  the  course  of 
a  ship ;  although  there  is  no  reason  to  suppose,  in  either  case,  that 
our  confidence  is  more  than  reasonable  and  judicious;  for  we  find 
in  nature  no  ultimate  or  final  reason  why  the  current  should  modify 
the  ship's  course,  or  why  the  environment  of  cats  should  modify 
their  structure,  except  that  the  fact  is  so.  Neither  do  we  find  in 
nature  any  explanation  of  cats  which  seems  to  us  perfectly  satis- 
factory to  mice. 

It  is  obvious,  however,  that  in  so  far  as  natural  selection 
accounts  for  all  that  is  distinctive  or  specific  in  the  structure  of 
living  things,  it  accounts,  at  the  same  time  and  to  exactly  the 
same  degree,  for  all  that  their  structure  does ;  and  that  the  web 
the  spider  makes  out  of  silk  is  no  harder  to  understand  than  the 
web  the  radiolarian  makes  out  of  protoplasm. 

So  far  as  Paley's  reasoning  concerns  the  zoologist,  it  is  a  trea- 
tise on  the  minor  premise  of  his  argument ;  for  no  one  in  his  day 
seems  to  have  thought  that  the  major  premise  needs  defence  or 
is  open  to  attack,  although  the  modern  zoologist  must  ask  whether 
we  are  sure  that  nothing  but  mind  accounts  for  watches.  In 
science  we  hold  a  thing  accounted  for  when,  certain  conditions 
being  given,  we  have  every  reason  to  expect  it;  and  Paley's 
major  premise  —  that  nothing  but  mind  accounts  for  watches — is 
worthless,  if  the  conditions  which,  being  given,  are  good  reasons 
for  expecting  watches,  are  physical. 

If  a  watchmaker  were  to  tell  us  he  was  so  distracted  by  care 
or  grief  that  he  did  not  know  what  he  was  about  when  he  made 
the  watch,  no  one  would  think  this  incredible ;  for  we  are  familiar 
with  the  unconscious  performance  of  equally  delicate  and  com- 
plicated and  definite  series  of  bodily  movements,  as  in  piano 
playing ;    nor  would  we  see  any  reason   to   doubt   the  assertion  of 


26o  THE  FOUNDATIONS  OF  ZOOLOGY 

the  members  of  a  church  choir  that  they  have  been  absorbed  in 
trivial  gossip  while  producing  solemn  harmony. 

We  all  know  the  feeling  of  surprise  that  the  time  has  passed 
and  that  so  much  has  been  done  after  an  hour  of  absorbed  study ; 
and  many  profound  thinkers  on  abstract  subjects  assure  us  that 
their  best  efforts  in  reasoning  are  those  which  go  on  in  ecstatic 
unconsciousness  of  self  or  of  the  intellectual  process.  I  imagine 
many  a  thinker  grows  conscious  of  cold  feet  and  an  empty  stomach 
before  he  becomes  aware  what  he  has  been  about  or  how  hard  he 
has  worked. 

It  may  be  said  that  while  the  piano  player,  or  even  the  watch- 
maker, might  carry  on  their  acquired  arts  unconsciously,  the 
training  which  has  set  apart  and  bound  together  the  series  of 
bodily  movements  was  accompanied  by  conscious  attention,  but 
there  is  no  reason  to  suppose  that  the  mere  repetition  of  these 
acts  would  not  give  the  same  result  if  it  could  be  brought  about  in 
unconsciousness ;  for  all  teachers  and  all  good  students  know  that 
the  effort  to  attend  is  more  difficult  than  the  mere  act  of  acquisition. 
Training  is  most  valuable  and  most  rapid  when  attention  comes 
without  conscious  effort ;  when  the  brain  is  a  passive  recipient. 

No  one  except  the  Lamarckians  supposes  that  training  gives 
the  watchmaker  any  new  muscles  or  nerves,  or  that  it  enables 
him  to  execute  any  bodily  movements  which  are  not  within  the 
reach  of  any  other  normal  human  being  whose  muscles  are 
equally  plastic  and  delicate  and  definite  in  action.  We  have 
already  seen,  page  60,  that  physical  training  is  beneficial  only  sa 
far  as  structural  adjustments  for  bringing  about  improvement  by 
use  already  exist,  and  that  it  corrects  our  actions  by  converting 
confused  and  perplexed  movements  into  exact  and  definite  ones ; 
nor  does  there  seem  to  be  any  good  reason  to  believe  that  the 
case  is  any  different  when  mental  nurture  is  in  question,  or  to  be- 
lieve that  mental  powers  which  come  with  training  are  different 
in  kind  from  those  that  "  come  by  nature." 

"  Newton  said  that  he  made  his  discoveries  by  intending  his 
mind  on  the  subject ;  no  doubt,  truly."  "  But  to  equal  his  suc- 
cess," says  Huxley,  "  one  must  have  the  mind  which  he  intended. 
Forty  lesser  men  might  have  intended  their  minds  till  they 
cracked,  without  any  like  result." 


NATURAL  SELECTION  AND  NATURAL   THEOLOGY        261 

Fruits  and  vegetables  must  have  good  nurture  to  reach  perfec- 
tion, but  the  gardener  knows  his  labor  will  be  vain  unless  he 
starts  with  seed  which  is  adapted  by  nature  for  improvement  by 
judicious  nurture ;  and  while  it  is  hard  for  us  to  consider  the 
question  whether  the  arts  and  accomplishments  of  normal  men  are 
due  to  anything  else  than  training  and  education,  we  feel  no  such 
difficulty  when  the  faculties  of  abnormal  or  exceptional  individuals 
are  in  question ;  for  the  restriction  of  the  powers  of  idiots  is 
clearly  correlated  with  deficient  structure,  and  training  and  educa- 
tion are  so  obviously  incompetent  to  account  for  the  achievements 
of  men  of  genius  that  we  are  apt  to  believe  that  their  natural  or 
innate  powers  are  different  in  kind  from  anything  in  our  own  more 
commonplace  selves. 

"  The  child  who  is  impelled  to  draw  as  soon  as  it  can  hold  a 
pencil ;  the  Mozart  who  breaks  out  into  music  as  early ;  the  boy 
Bidder  who  worked  out  the  most  complicated  sums  without  learn- 
ing arithmetic ;  the  boy  Pascal  who  solved  Euclid  of  his  own  con- 
sciousness,—  all  these,"  says  Huxley,  "may  be  said  to  have  been 
impelled  by  instinct  as  much  as  the  beaver  or  the  bee.  And  the 
man  of  genius  is  distinct  from  the  man  of  mere  cleverness,  by 
reason  of  the  working  in  him  of  strong  innate  tendencies  —  which 
cultivation  may  improve,  but  which  it  can  no  more  create  than 
horticulture  can  make  thistles  bear  figs.  Art  and  industry  may 
get  much  music,  of  a  sort,  out  of  a  penny  whistle ;  but  when  all  is 
done,  it  has  no  chance  against  an  organ." 

It  is  most  important  to  bear  in  mind  that  while  some  animals 
acquire  only  slowly,  and  after  long  training  and  practice,  faculties 
of  which  others  are  born  fully  possessed,  there  does  not  seem  to 
be  any  corresponding  difference  in  the  excellence  or  in  the  use- 
fulness of  these  faculties,  or  in  those  coordinations  among  them 
which  fit  their  possessor  for  useful  and  beneficial  response  to  the 
order  of  nature  in  the  outer  world. 

Many  birds  and  some  mammals  have  perfect  use  of  their 
senses,  and  have  all  their  muscular  movements  perfectly  coor- 
dinated at  birth  ;  while  others  —  kittens,  for  example  —  are  born 
blind,  all  their  movements  are  as  vague  and  aimless  as  those  of  the 
human  infant,  and  even  when  they  are  half  grown,  each  deter- 
minate  movement   in    their   frolics   is   accompanied    by  many  pur- 


262  THE  FOUNDATIONS   OF  ZOOLOGY 

poseless  and  uncoordinated  movements  in  all  parts  of  the  body  ; 
but  it  would  be  difficult  to  show  that  the  vision  of  a  dog,  which 
is  slowly  "acquired"  during  early  puppyhood,  or  the  coordina- 
tions between  it  and  the  movements  of  the  body,  is  any  more 
perfect,  or  any  more  useful  as  a  means  for  adjusting  action  to 
the  external  world,  than  that  of  the  wild  lamb  which,  in  less 
than  five  seconds  after  its  birth,  was  seen  by  Hudson  to  run 
freely  at  its  mother's  side,  as  she  started  off  at  a  brisk  trot  after 
the  flock ;  or  the  jacana  which,  as  the  egg  which  he  held  in  his 
hand  parted,  leaped  from  the  cracked  shell,  and  from  his  hand, 
into  the  water,  and  "  swimming  rapidly  to  a  small  mound,  and 
escaping  from  the  water,  concealed  itself  in  the  grass,  lying  down 
and  perfectly  motionless  like  a  young  plover." 

Spalding  tells  us  that  when  he  placed  a  chick  which  had  been 
blindfolded  at  birth,  on  rough  ground,  in  sight  of  a  hen,  "  it  started 
off  towards  the  hen,  displaying  as  keen  a  perception  of  the  qual- 
ities of  the  outer  world  as  it  was  ever  likely  to  possess  in  after 
life.  It  never  required  to  knock  its  head  against  a  stone  to  dis- 
cover that  there  was  no  road  that  way.  It  leaped  over  the  smaller 
obstacles  that  lay  in  its  path,  and  ran  round  the  larger,  reaching 
the  mother  in  as  nearly  a  straight  line  as  the  nature  of  the  ground 
would  permit.  This,  let  it  be  remembered,  was  the  first  time  it 
had  ever  walked  by  sight." 

The  coordination  between  tactile  and  muscular  impressions, 
and  those  we  get  through  the  eyes,  which  enables  us  to  walk  with 
sure  feet,  by  sight,  among  the  obstacles  which  beset  our  path 
through  the  world,  comes  with  training  which  is  accompanied  by 
conscious  judgment,  but  it  would  be  difficult  to  show  that  human 
sight  is  superior  in  any  way  to  that  of  birds ;  although  the  newly 
hatched  bird  may  coordinate  its  visual  and  tactile  and  muscular 
impressions  as  it  runs,  and  may  be  able,  before  its  first  sally  into 
the  world  is  fairly  begun,  to  maintain  its  balance  on  rough  ground, 
to  leap  over  small  obstacles,  to  go  around  larger  ones,  and  to  fitly 
adjust  its  actions  to  the  invisible  properties  which  are  associated, 
in  course  of  nature,  with  visible  ones. 

"  A  chick  two  days  old,"  says  Morgan,  "  had  learned  to  pick 
out  pieces  of  yolk  from  others  of  white  of  Q.gg.  I  cut  little  bits 
of  orange  peel  of  about  the  same  size  as  the  pieces  of  yolk,  and 


NATURAL   SELECTION  AND  NATURAL    THEOLOGY         263 

one  of  them  was  soon  seized,  but  at  once  relinquished,  the  chick 
shaking  his  head.  Seizing  another,  he  held  it  for  a  moment  in 
his  bill,  but  then  dropped  it  and  scratched  at  the  base  of  his  beak. 
This  was  enough ;  he  could  not  again  be  induced  to  seize  a  piece 
of  orange  peel.  The  obnoxious  material  was  now  removed,  and 
pieces  of  yolk  of  Q.gg  substituted,  but  they  were  left  untouched, 
being  probably  mistaken  for  orange  peel.  Subsequently,  he  looked 
at  the  yolk  with  hesitation,  but  presently  pecked  doubtfully,  not 
seizing  but  merely  touching,  then  he  pecked  again,  seized,  and 
swallowed." 

The  words,  as  they  are  here  quoted,  describe  the  facts  as  if 
they  were  known  to  be  accompanied  by  consciousness,  and  to  be 
in  all  respects  like  human  actions ;  and  as  words  are  adapted  to 
human  needs,  this  is  hard  to  avoid,  although  it  is  so  obviously 
impossible  to  say  whether  the  chick  is  conscious  or  not,  that  Mor- 
gan's assertion  that  his  study  of  young  chicks  shows  that  they 
soon  learn  what  is  good  to  eat  and  what  is  unpleasant,  and  rapidly 
associate  the  appearance  with  the  taste,  would  be  more  accurate 
if  he  had  confined  himself  to  some  such  statement  as  that  his 
studies  teach  that  they  rapidly  acquire  power  to  respond  to  visual 
stimuli  by  actions  adjusted  to  those  flavors  which  are  associated, 
in  course  of  nature,  with  certain  optical  properties.  While  the 
restriction  of  our  descriptions  of  the  actions  of  animals  to  words 
which  have  no  subjective  implications  would  be  intolerable  to  the 
reader  and  well-nigh  impossible  to  the  writer,  we  must  discriminate, 
so  far  as  possible,  what  we  really  learn  by  observation  from  what 
we  infer  from  the  analogy  of  our  own  actions.  The  important 
point  is,  that  whether  actions  like  those  of  the  new-born  lamb  are 
conscious  or  unconscious,  they  are  not  determined  by  conscious- 
ness, but  are  the  outcome  of  innate  congenital  structure ;  although, 
so  far  as  their  fitness  for  the  needs  of  the  animal  goes,  they  are 
in  no  way  inferior  to  actions  which  we  acquire  only  after  long 
training  which  is  accompanied  by  consciousness  and  attention  and 
intellectual  apprehension  of  the  desired  end. 

If  adaptations  like  the  muscular  coordinations  of  the  new- 
born lamb,  which  are  manifested  without  previous  experience  of 
their  use,  are  as  perfect  and  as  useful  as  those  which  are  slowly  ac- 
quired  by  long  training  accompanied   by  conscious  effort   and   by 


264  THE  FOUNDATIONS   OF  ZOOLOGY 

rational  apprehension  of  the  desired  end,  like  the  muscular  coordi- 
nations involved  in  making  a  watch,  are  we  not  forced  to  ask  the 
question  whether  we  can  be  sure  that  the  mental  states  which  have 
accompanied  the  watchmaker's  training  are  anything  more  than 
the  occasion  of  this  training,  or  the  stimulus  under  which  it  exhibits 
itself  ?  Is  it  any  harder  to  believe  an  imperfect  watch  or  a  rough, 
unfinished  part  of  a  watch  might  be  made  unconsciously  than  it  is 
to  believe  a  finished  watch  might  be  made  in  the  same  way?  If 
a  perfect  art  may  be  carried  on  unconsciously,  when  attention  is 
otherwise  occupied,  why  might  not  each  imperfect  step  in  its  grad- 
ual acquisition  be  taken  when  all  conscious  knowledge  of  the  pro- 
cess is  lost  through  absorption  in  the  work  ?  The  question  is  not 
whether  men  make  watches  voluntarily,  for  this  all  must  admit, 
even  if  we  see  reason  to  ask  whether  their  unconscious  produc- 
tion is  impossible. 

Whether  we  can  answer  it  or  not,  the  progress  of  zoology  has 
forced  us  to  ask  anew  the  old  question  whether  a  watch  may  not 
be  part  of  the  chain  of  physical  causation  just  as  truly  as  the 
spider's  web  or  the  cat.  Thoughtful  men  in  times  long  past  have 
asked  this  question  in  one  form  or  another  without  finding  any 
answer  which  could  command  general  assent,  and  while  we  may  be 
no  more  able  to  solve  it,  it  is  plain  that  the  discovery  of  natural 
selection  has  put  the  matter  in  a  new  light. 

If,  fifty  years  ago,  one  had  asserted  that  there  can  be  no  causal 
relation  between  the  mechanism  of  the  watch  and  the  movements 
of  the  earth,  except  that  which  is  found  in  the  thinking  minds  of 
those  by  whom  watches  are  invented  and  made,  I  do  not  suppose 
any  one  could  then  show  the  mistake  in  this  assertion ;  but  Dar- 
win and  Wallace  have  shown  that  such  a  relation  actually  exists, 
in  the  external  world,  and  as  independent  as  the  metal  in  the 
watch  of  human  thinkers.  Watches  help  the  watchmaker  to  hold 
his  own  in  the  struggle  for  existence  and  to  make  and  keep  a 
place  in  a  crowded  world  for  himself  and  for  his  family,  pre- 
cisely as  the  spider's  web  helps  the  spider.  While  the  external 
world  of  men  is  incomparably  more  vast  and  diversified  than  that 
of  cats,  the  adjustment  of  our  actions  to  the  flight  of  time  is  use- 
ful and  important  to  us  just  as  adjustment  to  the  life  of  mice  is 
useful    and    important   to    cats ;    for   the   lives   of   thousands    hang 


NATURAL  SELECTION  AND  NATURAL    THEOLOGY         265 

each  day  upon  the  accuracy  of  the  ship's  chronometer  or  on  that 
of  the  watch  of  the  railway  engineer. 

The  Duke  of  Argyll  tells  us  ("  Reign  of  Law  "  p.  35)  the  method 
of  creation  by  means  of  which  the  purpose  of  the  serpent's  poison 
is  carried  into  effect,  is  utterly  unknown. 

"Take  one  instance  out  of  a  million.  The  poison  of  a  deadly 
snake  —  let  us  for  a  moment  consider  what  this  is.  It  is  a  secre- 
tion of  definite  chemical  properties  which  have  reference,  not  only 
—  not  even  mainly  —  to  the  organism  of  the  animal  in  which  it 
is  developed,  but  specially  to  the  organism  of  another  animal 
which  it  is  intended  to  destroy.  Some  naturalists  have  a  vague 
notion  that,  as  regards  merely  mechanical  weapons  or  organs  of 
attack,  they  may  be  developed  by  use,  —  that  legs  may  become 
longer  by  fast  running,  teeth  sharper  and  longer  by  much  biting. 
Be  it  so  ;  this  law  of  growth,  if  it  exist,  is  but  itself  an  instru- 
ment whereby  purpose  is  fulfilled.  But  how  will  this  law  of 
growth  adjust  a  poison  in  one  animal  with  such  subtle  know- 
ledge of  the  organization  of  another  that  the  deadly  virus  shall  in 
a  few  minutes  curdle  the  blood,  benumb  the  limbs,  and  rush  in 
upon  the  citadel  of  life .-'  There  is  but  one  explanation,  —  a  Mind 
having  minute  and  perfect  knowledge  of  the  organization  of  both, 
has  designed  the  one  to  be  capable  of  inflicting  death  upon  the 
other.  The  mode  of  secretion  by  which  this  purpose  is  carried 
into  effect  is  utterly  unknown." 

Belief  that  this  adjustment,  and  others  like  it,  have  been 
produced  by  the  inheritance  of  the  effects  of  use,  is,  as  the  Duke 
of  Argyll  points  out,  a  notion  too  vague  to  have  any  value ;  but  since 
natural  selection  is  discovered,  no  one  can  assert  that  there  is  no 
scientific  explanation ;  for  the  snake  which  has  power  to  destroy 
its  enemies  has  such  an  advantage  in  the  struggle  for  existence 
that  its  survival  is  no  harder  to  understand  than  any  other  natural 
phenomenon. 

The  question  that  faces  the  modern  teleologist  is  not  whether 
the  contrivances  of  man  and  the  adjustments  of  living  nature  are 
useful,  for  this  all  must  admit ;  but  whether  the  snare  of  the 
fowler  gives  any  clearer  or  any  different  evidence  of  contriv- 
ance than  that  given  by  the  bird  in  whose  sight  it  is  spread  in 
vain. 


266  THE  FOUNDATIONS   OF  ZOOLOGY 

If  we  give  a  negative  answer  to  questions  like  this,  it  is  clear 
that  belief  that  the  works  of  nature  prove  design  by  their  resem- 
blance to  human  contrivances  has  indeed  received  its  death-blow ; 
not  because  Paley's  analogy  breaks  down,  but  because  it  becomes 
impregnable. 

Natural  selection  forces  us  to  reconsider  the  argument  from 
the  analogy  of  human  contrivances,  not  because  it  shows  that 
the  eye  and  the  cat  and  the  hinge  of  the  bivalve  shell  have 
come  about  in  order  of  nature ;  but  because  it  gives  to  human 
contrivances  a  significance  of  which  Paley  never  dreamed,  and 
because  it  forces  us  to  ask  whether  the  hunter  who  contrives  a 
net  furnishes  any  different  basis  for  analogy  with  the  works  of 
nature  than  the  fish  that  contrives  to  get  the  bait  without  danger, 
or  the  spider  and  the  sundew  which  also  spread  their  snares,  or 
the  hydroid  with  its  net  of  poisoned  tentacles,  or  the  radiolarian 
with  its  web  of  protoplasm. 


LECTURE    XI 

PALEY,    AND    THE   ARGUMENT    FROM    CONTRIVANCE 


LECTURE   XI 

PALEY,   AND  THE  ARGUMENT  FROM   CONTRIVANCE 

Paley  sometimes  argues  that  it  is  because  watches  are  made 
by  men  that  they  prove  design ;  while  in  other  places,  he  holds 
that  it  because  they  are  so  put  together  as  to  point  out  the 
hours  of  the  day. 

We  must  therefore  ask  what  bearing  natural  selection  has  on 
this  statement  of  his  argument :  — 

(i)  Living  things,  and  their  works,  such  as  watches,  exhibit 
peculiar  evidence  of  usefulness. 

(2)  Evidence  of  usefulness  is  evidence  of  design. 

(3)  Living  things  and  their  works  exhibit  peculiar  evidence  of 
design. 

If  it  is  true  that  watches  come  about  in  order  of  nature,  and 
are  so  joined,  by  natural  causation,  to  the  movements  of  the  earth 
that  no  one  who  knows  all  the  data  would  have  the  least  reason 
to  expect  that  men  should  not  make  and  sell  and  buy  and  use 
them,  this  may  well  raise  a  doubt  whether  the  contrivance  of 
man  is  any  interruption  to  the  order  of  nature ;  but  a  moment's 
thought  shows  that  it  by  no  means  does  away  with  the  teleologi- 
cal  problem,  or  makes  it  any  easier  to  solve ;  for  it  is  still  as  true 
as  ever  it  was  that  watches  do  not  come  about  without  human 
makers,  and  that  they  are  useful  to  mankind  and  help  to  preserve 
the  human  species  from  destruction. 

If  the  structure  and  orderly  history  of  such  things  as  eyes, 
and  cats,  and  spiders'  webs,  and  watches  were  all  \vc  discover  in 
them,  we  might  say  these  things  are  no  harder  to  understand  than 
inorganic  bodies  and  their  movements ;  for  if  living  things  are 
continually  bringing  about  rearrangements  of  inorganic  matter 
and  physical  energy,  like  watches,  which  never  come    about   with- 

269 


270  THE  FOUNDATIONS   OF  ZOOLOGY 

out  them,  lifeless  bodies  continually  do  the  same.  The  tide  pro- 
duces changes  of  matter  and  energy  which  would  never  have  been 
brought  about  in  a  tideless  ocean,  such  as  the  gradual  conversion 
of  the  earth's  motion  of  rotation  into  friction  between  sea  and 
land ;  but  no  one  finds,  in  the  friction  which  has  brought  the 
moon  to  rest  upon  its  axis,  anything  that  might  not  have  been 
expected.  If  living  bodies  did  no  more  than  to  bring  about  things 
which  would  never  happen  without  them,  no  one  could  find  in 
this  any  essential  difference  between  them  and  lifeless  bodies ;  but 
we  do  find  a  most  significant  difference  in  the  sort  of  things  they 
bring  about,  as  Aristotle  pointed  out  long  ago.  "  To  say  what 
are  the  ultimate  substances  out  of  which  an  animal  is  formed  is 
no  more  sufficient "  now  than  it  was  two  thousand  years  ago ;  for 
the  distinctive  things  that  are  brought  about  by  living  beings  are 
things  that  are  useful  to  the  beings  which  bring  them  about  or 
to  their  species ;  and  usefulness  implies  the  continued  existence  of 
the  user,  as  distinguished  from  the  things  that  are  used;  for  it 
does  not  consist  in  the  act  of  use,  but  in  something  that  comes 
after. 

The  words  "  survival  of  the  fittest "  are  meaningless  unless 
the  being  that  survives  the  selective  process  is  identical  with  the 
one  that  remains  fit  after  the  selective  process  has  acted ;  and 
belief  in  the  efficacy  of  natural  selection  involves  belief  in  that 
continuity  of  life  which,  in  the  form  we  know  most  intimately, 
we  call  personal  identity. 

Just  so  far  as  natural  selection  tends  to  break  down  the  dis- 
tinction between  the  contrivances  of  man  and  the  works  of  nature, 
just  so  far  does  it  show  that  the  distinction  between  subject  and 
object ;  the  distinction  which  is  the  fundamental  problem  of  all 
systems  of  philosophy  and  the  fundamental  postulate  of  most  sys- 
tems of  religion ;  the  distinction  between  self  and  not-self ;  is  co- 
extensive with  life.  Since  this  is  so,  may  we  not  still  say  with 
Paley:  "Marks  of  design  are  no  more  accounted  for  than  they 
were  before.  Our  going  back  ever  so  far  brings  us  no  nearer  to 
the  least  degree  of  satisfaction  upon  the  subject".'' 

As  the  human  child  seems,  so  far  as  we  can  ascertain,  to  gradually 
discover  its  continued  existence  through  consciousness  and  memory 
of  the  past,  we  are  apt  to  think  that  personal  identity  implies  con- 


PALEV,   AND    THE  ARGUMENT  FROM  CONTRIVANCE      2/1 

sciousness,  and  is  equivalent  to  intellectual  or  rational  sameness  or 
identity ;  but  a  moment's  thought  will  show  that  this  is  not  the  case, 
for  none  of  us  have,  or  know  whether  we  ever  had,  consciousness 
of  our  early  infancy,  our  birth,  or  our  embryonic  history,  although 
no  naturalist  can  admit  that  there  is  any  interruption  in  the  con- 
tinuity of  our  personal  existence  between  the  fertilized  ovum  and  old 
age,  for  while  birth  is  a  notable  event  in  the  history  of  man  and  of 
most  of  the  familiar  animals,  it  is  no  necessary  or  universal  stage 
in  the  development  of  organisms  in  general. 

Does  any  one  who,  while  unconscious,  has  undergone  a  surgical 
operation  doubt  whether  he  is  personally  identical  with  the  uncon- 
scious patient  ?  May  not  one  carry  to  the  verge  of  the  grave  the 
physical  or  mental  or  moral  effects  of  an  accident  which  occurred 
before  his  earliest  recollection  ? 

A  moment's  thought  shows  that  we  have  the  same  sort  of  reason 
for  belief  in  the  continued  existence  of  every  being  whose  acts  are 
useful  to  itself  or  to  its  species,  as  we  have  for  belief  in  our  own 
persistent  identity  through  much  of  our  own  history  ;  for,  as  Dr. 
Butler  pointed  out  long  ago,  "  we  should  really  think  it  self-evident 
that  consciousness  of  personal  identity  presupposes,  and,  therefore, 
cannot  constitute,  personal  identity ;  any  more  than  knowledge,  in 
any  other  case,  can  constitute  truth,  which  it  presupposes."  "To 
say  that  consciousness  of  our  continued  existence  makes  personal 
identity,  or  is  necessary  to  our  being  the  same  person,  is  to  say,"  as 
Butler  shows,  "  that  a  person  does  not  exist  a  single  moment,  or 
do  one  action,  but  what  he  can  remember;  indeed,  none  but  what  he 
reflects  upon."  "Present  consciousness  of  past  actions,"  says  Butler 
"is  not  necessary  to  our  being  the  same  person  who  performed  those 
actions,"  and  he  might  have  added  that  neither  is  past  consciousness 
necessary ;  for  it  is  not  necessary  that  the  acts  of  a  being  should  be 
rational  to  prove  personal  identity,  but  only  that  they  should  be  such 
that,  if  accompanied  by  mind,  they  would  be  rational.  For  all  we 
know  to  the  contrary  the  human  ovum  may  be  conscious,  and  so 
may  the  tree  be,  or,  for  that  matter,  the  stone ;  but  we  do  know  that, 
whether  living  beings  be  conscious  or  not,  they  so  respond  to  the 
changes  which  go  on  in  the  outer  world  that  our  reason  approves 
their  actions ;  and  it  is  their  fitness  itself,  not  their  consciousness  of 
it,  which  proves  their  continued  existence. 


2/2  THE  FOUNDATIONS   OF  ZOOLOGY 

For  all  we  know  the  properties  of  the  stone  may  be  useful  to  the 
stone,  and  for  all  we  know  the  stone  may  be  conscious  and  rational, 
but  these  words  mean  nothing  to  us  ;  although  we  can  see  clearly 
that  the  distinctive  properties  of  living  things  are  useful  to  them  or 
to  their  species.  If  it  is  said  that  words  which  mean  nothing  are 
nonsense,  and  that  we  are  not  to  talk  nonsense,  we  must  answer  that 
no  honest  confession  of  ignorance  can  be  nonsense,  and  that  the  bur- 
den of  proving  he  is  not  talking  nonsense  rests  with  him  who  asserts 
that  stones  are  not  conscious. 

So  far  as  I  am  aware  Butler  is  the  only  one  of  the  older  writers 
on  natural  theology  who  perceived  that  the  responsive  actions  of 
living  things  prove  that  all  living  things  have  personal  identity ; 
and,  whether  he  be  the  first  or  not,  his  reasoning  seems  conclusive, 
although  modern  science  cannot  permit  him  to  escape  any  of  the 
consequences  of  this  admission  by  asserting  that  trees  are  not  living 
things. 

"  Consider,"  he  says,  "  a  living  being  now  existing,  and  which 
has  existed  for  any  time  alive.  This  being  must  have  done  .  .  . 
what  it  has  done  .  .  .  formerly,  as  really  as  it  does  .  .  .  what  it 
does  .  .  .  this  instant.  All  these  actions  .  .  .  are  actions  ...  of 
the  same  living  being.  And  they  are  so  prior  to  all  consideration 
of  its  remembering  or  forgetting ;  since  remembering  and  forgetting 
can  make  no  alteration  in  the  truth  of  past  matters  of  fact.  And 
suppose  this  being  endowed  with  limited  powers  of  knowledge  and 
memory,  there  is  no  more  difficulty  in  conceiving  it  to  have  the 
power  of  knowing  itself  to  be  the  same  living  being  which  it  was 
some  time  ago,  of  remembering  some  of  its  actions,  sufferings,  and 
enjoyments,  and  forgetting  others,  than  in  conceiving  it  to  know 
or  remember  or  forget  anything  else."  ^ 

If  Butler  is  right,  if  consciousness  of  personal  identity  does 
not  make  but  presupposes  personal  identity,  we  may  consider  the 
continued  existence  of  living  things  quite  apart  from  the  question 
whether  they  know  their  continued  existence ;  but  personal  iden- 
tity is,  so  far,  a  phenomenon,  a  part  of  the  order  of  objective 
nature,  which  may  be  studied,   like  other  natural   phenomena,  by 

^The  reader  who  is  familiar  with  Butler  will  note  that  the  words  I  have  omitted  after 
"  done,"  and  in  other  places  are  "  suffered  and  enjoyed,"  for  the  argument  does  not  seem  to 
demand  any  opinion  as  to  the  extent  of  the  parallel  between  life  and  enjoyment  and  suffering. 


PALEY,   AND   THE  ARGUMENT  FROM  CONTRIVANCE      273 

Strictly  scientific  methods.  It  also  seems  clear  that  the  signifi- 
cance of  the  argument  from  contrivance  or  interference  with  the 
order  of  physical  nature,  turns  on  the  account  which  science  gives 
of  this  aspect  of  personal  identity;  for  the  discovery  of  natural 
selection  forbids  us  to  assert,  before  this  question  is  answered,  that 
the  evidence  of  contrivance  afforded  by  living  things  and  their 
works  is  different  from  that  which  is  afforded  by  inorganic  bodies 
and  their  movements,  inasmuch  as  it  shows  us  the  chain  of  physi- 
cal causation  which  joins  the  works  of  man  and  of  other  living 
beings  to  that  part  of  the  order  of  nature  to  which  they  are  adjusted. 

While  I  cannot  agree  with  those  enthusiastic  zoologists  who 
hold  that  life  has  been  proved  to  be  a  matter  of  physics  and 
chemistry,  modern  science  seems,  to  me,  to  demand  that  we  sus- 
pend judgment  upon  this  difficult  question,  and  wait  for  more 
evidence,  for  there  seems  to  me  to  be  no  better  basis  for  a  negative 
than  for  an  afifirmative  answer. 

If  science  furnishes  proof  that  the  continuity  of  life  is  not 
only  a  natural  phenomenon  but  a  physical  phenomenon,  which 
may  be  expressed  in  terms  of  physical  matter  and  mechanical 
energy,  then,  indeed,  the  argument  from  contrivance  has  received 
its  death-blow ;  for  we  can  no  longer  find,  in  the  actions  of  living 
things,  or  in  those  of  any  living  thing,  evidence  of  interference 
with  the  order  of  physical  nature.  If,  however,  the  answer  which 
science  gives  is  imperfect  or  indecisive,  then  I  think  we  must 
admit  that,  while  weakened  by  the  discovery  of  natural  selection, 
the  argument  from  contrivance  is  not  utterly  destroyed.  Finally,  if 
science  fails  to  throw  any  light  on  the  origin  and  meaning  of  per- 
sonal identity,  then  the  argument  from  contrivance  has  the  same 
value,  whatever  this  may  be,  that  it  had  before  natural  selection 
was  discovered. 

Two  hundred  and  fifty  years  ago  no  one  thought  of  asking 
whether  living  beings  ever  arise  out  of  dead  matter,  for  all  believed 
that  they  never  arise  in  any  other  way ;  and  that  this  may  be  illus- 
trated by  observing  how  quickly  dead  things,  like  dung  and  rotten 
meat  and  the  carcasses  of  dead  animals,  breed  maggots  and  flies 
under  the  influence  of  the  hot  sun. 

"  The  proposition  that  life  may,  and  does,  proceed  from  that 
which  has  no  life  was  held  alike  by  the  philosophers,  the  poets, 


2/4  THE  FOUNDATIONS  OF  ZOOLOGY 

and  the  people  of  the  most  enlightened  nations  eighteen  hundred 
years  ago ;  and  it  remained  the  accepted  doctrine  of  learned  and 
unlearned  Europe  through  the  Middle  Ages,  and  even  to  the 
seventeenth  century." 

It  is  clear  that  natural  selection  would  have  given  the  death- 
blow to  the  argument  from  contrivance  if  this  opinion  had  been 
well  founded ;  but  it  is  equally  well  known  that  the  progress  of 
science  has  shown  the  worthlessness  of  all  the  evidence  for  spon- 
taneous generation. 

In  my  opinion  the  second  alternative  is  most  consistent  with 
the  present  state  of  our  knowledge ;  for  while  the  discovery  of 
natural  selection  has  shown  how  all  the  endless  forms  of  life,  with 
all  their  admirable  and  wonderful  adjustments  to  the  diversity  and 
harmony  of  the  external  world,  may  have  arisen  from  a  common 
starting-point  in  some  primitive  organism,  so  simple  and  so  homo- 
geneous that  its  production  out  of  inorganic  matter  does  not  seem 
improbable,  the  progress  of  our  knowledge  in  other  lines  has 
demonstrated  that,  as  a  matter  of  fact,  all  the  living  things  we 
know  do  arise  from  preexisting  living  things. 

The  demonstration  of  the  continuity  of  life  which  we  owe  to 
the  embryologists  and  histologists  of  modern  times,  and  to  the 
students  of  pathology  and  hygiene,  is  a  contribution  to  philosophy 
of  the  utmost  value  and  significance.  This  law  of  continuity  is  a 
discovery  as  real  as  the  law  of  natural  selection  itself,  for  we  now 
have  every  reason  to  believe,  not  only  that  personal  identity  is 
coextensive  with  life,  but  also  that  there  is  no  break  in  its  conti- 
nuity at  any  point  in  the  whole  history  of  life.  Every  living  thing 
on  earth,  and,  so  far  as  we  know,  all  that  have  ever  lived,  are 
personally  identical  with  the  primeval  living  being,  in  exactly 
the  same  sense  as  the  mature,  conscious,  rational  man  is  person- 
ally identical  with  the  human  foetus  and  the  new-born  babe. 

The  history  of  the  great  modern  discovery  of  the  continuity 
of  life  has  been  written  by  so  many  able  students  that  there  would 
be  no  reason  to  review  any  part  of  it  here  if  the  share  of  that 
great  investigator  and  thinker,  William  Harvey,  in  the  demonstra- 
tion that  the  facts  are,  in  this  matter,  opposed  to  venerable  author- 
ity, had  not  been  so  strangely  misunderstood  and  misrepresented 
as  to  call  for  correction. 


PALEV,   AND    THE  ARGUMENT  FROM  CONTRIVANCE      2/5 

No  less  careful  a  writer  than  Huxley,  himself  an  ardent 
admirer  and  diligent  student  of  Harvey,  tells  us  ("  Encyclopaedia 
Britannica,"  article  Evohctioti,  p.  746)  that  "  Harvey  believed  as 
implicitly  as  Aristotle  did  in  the  equivocal  generation  of  the 
lower  animals.  Harvey  shared  the  belief  of  Aristotle,  whose  writ- 
ings he  often  quotes,  and  of  whom  he  speaks  as  his  precursor 
and  model,  with  the  generous  respect  with  which  one  genuine 
worker  should  regard  another  —  that  such  germs  may  arise  by  a 
process  of  '  equivocal  generation '  out  of  non-living  matter " ;  but 
I  am  by  no  means  confident  that  this  assertion  does  justice  to 
Harvey,  or  that  the  quotations  from  Aristotle  prove  anything 
except  that  Harvey  was  not  fully  prepared  to  demonstrate  their 
error.  While  Huxley  ("Spontaneous  Generation,"  1870)  tells  us 
he  can  find  no  justification  for  the  notion  that  Harvey  doubted 
the  occurrence  of  spontaneous  generation,  I  find  ample  evidence 
that  he  had  made  many  experiments  which  led  him  to  distrust 
the  opinion  which  prevailed  in  his  day ;  although  he  may  not 
have  felt  fully  armed  to  attack  the  teachings  of  "  my  leader,  Aris- 
totle, .  .  .  one  of  nature's  most  diligent  inquirers,  .  .  .  whose  author- 
ity has  such  weight  with  me  that  I  never  think  of  differing  from  him 
inconsiderately." 

It  is  true  that  he  quotes  without  comment,  and  often  without 
credit,  the  very  words  in  which  Aristotle  afifirms  spontaneous  gen- 
eration;  but,  as  an  offset  to  this,  he  tells  us  explicitly  (Exercise  the 
forty-first)  that  he  shall  show  in  another  place  "that  many  animals, 
especially  insects,  arise  and  are  propagated  from  elements  and 
seeds  so  small  as  to  be  invisible  (like  atoms  flying  in  the  air), 
scattered  and  dispersed  here  and  there  by  the  winds ;  and  yet 
these  animals  are  supposed  to  have  arisen  spontaneously,  or  from 
decomposition,  because  their  ova  are  nowhere  to  be  found." 

He  was  far  too  courteous  and  too  cautious  to  have  ventured 
to  criticise  "The  Philosopher,"  to  even  this  extent  without  scien- 
tific evidence,  and  in  Exercise  the  sixty-ninth  he  tells  us  why  his 
researches  were  never  published.  . 

"  Let  gentle  minds  forgive  me,"  he  asks,  "  if,  recalling  the 
irreparable  injuries  I  have  suffered,  I  here  give  vent  to  a  sigh. 
This  is  the  cause  of  my  sorrow :  whilst  in  attendance  on  his 
majesty,    the    king,    during    our    late    trouble    and    more    than    civil 


2/6  THE  FOUNDATIONS   OF  ZOOLOGY 

wars,  not  only  by  the  permission  but  by  the  command  of  the 
Parliament,  certain  rapacious  hands  stripped  not  only  my  house 
of  its  furniture,  but  what  is  subject  for  far  greater  regret  with 
me,  my  enemies  abstracted  from  my  museum  the  fruits  of  many 
years  of  toil. 

"Whence  it  has  come  about  that  many  observations,  particularly 
on  the  generation  of  insects,  have  perished,  with  detriment,  I  vent- 
ure to  think,  to  the  republic  of  letters." 

These  extracts  seem  to  prove  that,  while  it  is  easy  to  find  in 
his  writings  many  passages  in  which  belief  in  spontaneous  gen- 
eration is  asserted,  usually  in  the  words  of  Aristotle,  the  validity 
of  these  beliefs  is  admitted  out  of  courtesy  to  Aristotle  and  for 
the  sake  of  the  argument,  as  a  subject  on  which  he  is  not  yet 
prepared  to  make  his  researches  public. 

If  the  reader  who  is  interested  will  turn  to  the  title-page  of 
the  original  edition  of  Harvey's  Essay  on  Generation,  he  will  note 
that  not  only  deer  and  human  infants  and  serpents,  but  insects,  as 
well,  are  escaping  from  the  bursting  ^g^  which  Jove  holds  in  his 
hand. 

As  that  practical  old  traveller,  Herodotus,  suggests  that  the 
frogs  and  insects  which  are  commonly  supposed  to  be  generated 
out  of  the  mud  and  slime  of  the  Nile,  may,  perhaps,  come  from 
eggs,  Aristotle's  readiness  to  believe  in  their  spontaneous  genera- 
tion is  hard  to  understand  until  we  discover  that  the  reason  why 
he  saw  nothing  suspicious  in  the  generation  of  animals  from  dead 
and  decomposing  organic  matter  is  to  be  found  in  his  belief  that 
all  generation  takes  place  in  the  same  way. 

Every  conception,  according  to  Aristotle,  is  a  case  of  sponta- 
neous generation  out  of  excrement,  and  he  regards  the  generation 
of  insects  out  of  putrescent  slime  as  a  simple  example,  what 
we  should  now  call  a  primitive  type,  of  generation  in  general,  by 
comparison  with  which  more  complicated  and  obscure  cases  are 
to  be  interpreted. 

As  a  bloody  substance  is  discharged  at  intervals  from  the 
reproductive  organs  of  the  human  female,  he  believed  that  the 
mammalian  embryo  is  generated  out  of  this  excrement,  just  as 
other  animals  are  generated  out  of  decomposing  matter  of  other 
kinds.     As  heat  causes  milk  to  curdle,  so  he  says  the  geniture  of 


PALEV,   AND   THE  ARGUMENT  FROM  CONTRIVANCE      2/7 

the  male  causes  the  purest  part  of  the  catamenia  to  set  and  form 
a  coagulum  like  curdled  milk,  and  he  believes  that  the  embryo 
arises  from  this  coagulum  by  spontaneous  generation. 

One  modification  or  another  of  this  opinion  continued  to  pre- 
vail until  Harvey's  day,  and  it  is  plain  that  experiments  on  the 
generation  of  insects  was  mere  skirmishing  on  the  outposts  of  the 
problem  until  the  belief  in  the  generation  of  the  higher  animals 
out  of  excrement  had  been  corrected  ;  and  Harvey  wisely  concen- 
trated his  attention  on  this  citadel  of  the  belief  in  the  origin  of 
living  things  from  dead  matter.  If  a  mass  of  excrement  exists  in 
the  uterus  immediately  after  a  fertile  union,  this  ought  to  be  dis- 
coverable; and  Harvey,  a  true  scientific  investigator,  set  to  work 
to  hunt  for  it  without  a  microscope,  more  than  two  hundred  years 
before  the  discovery  of  the  human  ovum  by  Von  Baer. 

His  facilities  for  making  the  search,  and  its  results,  are  best 
described  in  his  own  words.  He  was  the  attending  physician  of 
the  king  of  England,  and  he  tells  us  "it  was  customary  with 
his  Serene  Majesty,  King  Charles,  after  he  had  come  to  man's 
estate,  to  take  the  diversion  of  hunting  almost  every  week,  both  for 
the  sake  of  finding  relaxation  from  graver  cares  and  for  his  health ; 
the  chase  was  principally  the  buck  and  the  doe,  and  no  prince 
in  the  world  had  greater  herds  of  deer.  This  gave  me  an  oppor- 
tunity of  dissecting  these  animals  almost  every  day  during  the 
whole  season  when  they  were  rutting,  taking  the  male,  and  falling 
with  young.  I  had  occasion  so  often  as  I  desired  it  to  examine 
and  study  all  their  parts,  particularly  those  devoted  to  the  offices 
of  generation." 

His  researches  had  a  very  definite  result.  Repeated  dissections 
performed  in  the  course  of  the  month  of  October,  both  before 
the  rutting  season  was  over  and  after  it  had  passed,  never  showed 
a  trace  of  coagulated  blood  or  excrement  of  any  sort.  Neither 
the  bloody  coagulum  of  Aristotle  nor  the  geniture  of  the  medical 
men  has  any  existence.  The  "conception"  which  should  be  discov- 
erable, if  their  teachings  are  correct,  cannot  be  found  when  search 
is  made  for  it,  and  actual  observation  shows  that  the  opinion  which 
had  been  current  for  nearly  two  thousand  years  is  erroneous  and 
fanciful. 

The  keepers  and  huntsmen    said   that   "I    was   both    deceiving 


2/8  THE  FOUNDATIONS  OF  ZOOLOGY 

myself  and  had  misled  the  king,  and  that  there  must  of  necessity 
be  something  of  the  '  conception '  to  be  found  in  the  uterus. 
These  men,  however,  when  I  got  them  to  bring  their  own  eyes 
to  the  inquiry,  gave  up  the  point."  Harvey  tells  us  the  king  fully 
appreciated  the  value  of  the  investigation,  and  in  order  that  this 
important  question  might  be  the  more  satisfactorily  settled  in  all 
time  to  come,  provided  means  for  isolating  the  does  and  thus 
proving  that  there  was  no  error  as  to  the  fact  of  conception ; 
but  the  physicians  were  still  unconvinced,  and  "  held  it  among 
their  impossibilities  that  any  conception  should  ever  be  found 
without  the  presence  of  excrement  in  one  form  or  another."  But 
the  man  who  had  proved  the  error  of  their  teachings  regarding 
the  function  of  the  heart  and  blood-vessels  had  little  tolerance 
for  their  belief  in  anything  they  were  unable  to  demonstrate. 

If  they  had  insisted  that  Harvey's  resources  were  inadequate, 
and  that  the  conception  for  which  he  sought  is  a  living  being 
too  minute  to  be  found  by  such  rough  means,  but,  to  use  the  word 
he  employs  in  another  place,  "  like  the  youth  who  comes  of  age, 
made  independent  even  from  its  first  appearance,  as  the  acorn 
taken  from  the  oak,  and  the  seeds  of  plants  in  general,  are  no 
longer  to  be  considered  parts  of  the  tree  or  herb  that  supported 
them,  but  things  made  in  their  own  right,  and  which  already 
enjoy  life,"  we  now  know  they  would  have  been  in  the  right.  But 
his  proof  of  the  non-existence  in  the  uterus  of  the  doe  of  the  excre- 
ment, of  which  they  had  taught  that  the  conception  consists,  is 
conclusive. 

Harvey  did  not  stop  here,  however;  for  he  made  careful  obser- 
vations on  the  fowl,  the  rabbit,  the  dog,  and  on  many  other  animals, 
and  proved  that  none  of  them  are  generated  out  of  excrement  or 
decomposing  matter;  that  there  is  no  basis  in  nature  for  Aristotle's 
opinion  or  that  of  the  medical  men  of  Harvey's  day,  and  that  all 
their  teachings  break  down  when  brought  to  the  test  of  actual 
observation. 

It  is  no  small  thing  to  prove  the  error  of  the  belief,  which  had 
been  current  for  nearly  two  thousand  years,  and  is  even  now  embod- 
ied, through  a  quotation  from  St.  Paul,  in  our  burial  service,  that 
all  forms  of  reproduction  are,  at  bottom,  examples  of  spontaneous 
generation   out   of  dead  putrescent   matter.      This   Harvey  accom- 


PALEV,   AND   THE  ARGUMENT  FROM  CONTRIVANCE      279 

plished  by  methods  which  are  rigorously  scientific  ;  and  no  scien- 
tific generalization,  not  even  natural  selection  itself,  has  more 
profound  significance  than  the  great  natural  law  which  modern  stu- 
dents have  built  upon  his  foundation ;  for  we  now  know  that  there 
is  no  break  in  the  continuity  of  life,  and  that  every  living  thing 
with  which  we  are  acquainted  is  in  direct  unbroken  vital  continu- 
ity with  the  primeval  living  matter  of  pre-Cambrian  times. 

This  being  the  case,  is  it  not  plain  that,  so  far  as  the  ques- 
tion of  origin  is  concerned,  we  know  only  a  single  example  of 
life  ?  Our  knowledge  is,  in  this  respect,  a  single  experience  ;  and  it 
affords  no  basis  for  comparison  with  any  other  aspect  of  nature, 
or  for  scientific  generalization,  or  for  any  other  logical  process, 
either  positive  or  negative. 

So  far  as  I  can  see,  there  is  no  reason  why  we  should  not  say 
now  as  Huxley  said  before  natural  selection  was  discovered  :  "  It  may 
be  that,  by  and  by,  philosophers  will  discover  some  higher  laws  of 
which  the  facts  of  life  are  particular  cases,  —  very  possibly  they 
will  find  out  some  bond  between  physico-chemical  phenomena  on 
the  one  hand  and  vital  phenomena  on  the  other.  At  present  we 
assuredly  know  of  none ;  and  I  think  we  shall  exercise  a  wise 
humility  in  confessing  that,  for  us  at  least,  .  .  .  this  distinction  be- 
tween living  bodies  and  those  which  do  not  live  is  an  ultimate  fact." 

If  any  choose  to  believe  life  is  different  from  matter  and 
motion,  I  do  not  see  how,  in  the  present  state  of  our  knowledge, 
they  can  be  proved  wrong ;  nor  can  we  in  justice  charge  them 
with  belief  in  the  supernatural,  for  the  assertion  that  belief  in  that 
which  is  not  physical  is  belief  in  the  supernatural  is  not  reasoning 
until  every  natural  phenomenon  has  been  proved  to  be  physical; 
neither  is  there  any  more  reason  in  the  assertion  that  the  inde- 
structibility of  energy  disproves  spontaneity  even  if  some  form  of 
dead  matter  should  be  proved  to  respond  to  the  order  of  nature 
to  its  own  advantage,  like  living  things. 

On  the  other  hand,  it  seems  clear  that  we  can  give  no  reason 
for  disagreeing  with  those  who  believe  life  is  a  property  of  proto- 
plasm except  that  this  is  not  yet  proved.  Our  inability  to  con- 
ceive that  a  thought  or  a  response  can  be  a  property  of  matter 
is  no  reason  why  this  may  not  be  true.  So  far  as  I  can  discover, 
the  only  reason  why  we  are  able  to  conceive  that  weight  can   be 


28o  THE  FOUNDATIONS   OF  ZOOLOGY 

a  property  of  extended  bodies  is  the  fact  that  it  is  so ;  and  if  we 
had  the  same  sort  of  evidence  that  life  is  a  property  of  matter,  I 
do  not  see  why  this  might  not  be  equally  conceivable. 

I  have  no  sympathy  with  those  who  base  their  philosophical 
creed  on  their  hope  and  their  faith  that  we  shall  some  day  be  able 
to  see  our  way  from  the  physical  and  chemical  properties  of  pro- 
toplasm to  the  responsive  actions  of  living  things  as  clearly  as 
we  predict  the  movements  of  a  watch  from  the  form  of  its  parts, 
nor  have  I  any  more  sympathy  with  those  who,  on  what  seems 
to  me  an  equal  lack  of  proof,  live  in  the  hope  and  in  the  faith 
that  this  consummation  is  necessarily  and  forever  beyond  the  reach 
of  science ;  for  faith  and  hope  are  not  knowledge,  nor  a  creed 
science. 

"  Those  who  take  a  monistic  view  of  the  physical  world,"  says 
Huxley,  "  may  fairly  hold  abiogenesis  as  a  pious  opinion,  sup- 
ported by  analogy  and  defended  by  ignorance.  But,  as  matters 
stand,  it  is  equally  justifiable  to  regard  the  physical  world  as  a 
sort  of  dual  monarchy.  The  kingdoms  of  living  matter  and  of 
not-living  matter  are  under  one  system  of  laws,  and  there  is  a 
perfect  freedom  of  exchange  and  transit  from  one  to  the  other. 
But  no  claim  to  biological  nationality  is  valid  except  birth." 

The  assertion  that  there  can  be  but  one  order  of  things, 
because  it  is  so  much  neater  than  two,  is,  of  course,  unworthy 
the  name  of  argument. 

The  essential  characteristic  of  life  is  fitness.  A  living  organ- 
ism is  a  being  that  uses  the  world  around  it  for  its  own  good. 
I  for  one  am  unable  to  find,  in  inorganic  matter,  any  germ  of 
this  wonderful  attribute.  It  is  possible  that  after  chemistry  has 
given  us  protoplasm  this  may  be  shaped  by  natural  selection,  or 
some  other  purely  physical  influence,  into  persistent  adjustment 
to  the  shifting  world  around  it,  and  that  it  may  thus  become 
alive. 

Everything  is  possible  to  them  who  know  nothing ;  but  why 
should  we  believe  anything  on  this  matter  until  we  have  evidence .'' 

"  Knowledge  and  truth  may  be  in  us  without  judgment,  and 
we  may  have  judgment  without  them ;  yea,  the  acknowledgment 
of  ignorance  is  one  of  the  best  and  surest  testimonies  of  judgment 
that  I  can  find." 


PALEV,   AND   THE  ARGUMENT  FROM  CONTRIVANCE      28 1 

Of  one  thing  we  may  be  sure.  The  artificial  production  of 
protoplasm  would  not  be  a  solution  of  the  problem  of  life ;  since 
the  nature  of  this  problem  must  be  grasped,  in  all  its  length 
and  breadth,  with  all  its  difficulties,  before  we  can  hope  to  solve 
it;  for  the  transformation  of  the  truth  that  protoplasm  is  the 
physical  basis  of  life  into  a  dogmatic  assertion  that  life  is  the 
sum  of  the  physical  properties  of  protoplasm  is  no  solution. 

Life  cannot  go  on  without  food ;  and  we  may  say  that  bread 
is  the  staff  of  life;  but  the  influence  which  shapes  food  into  the 
specific  structure  of  an  organism  exquisitely  adapted  to  the  con- 
ditions of  the  world  around  it  is  to  be  sought  somewhere  else 
than  in  the  properties  of  bread. 

One  of  the  distinctive  characteristics  of  this  organizing  influ- 
ence is  that  it  may  exist  without  any  corresponding  visible  organi- 
zation ;  for  while  the  germ  which  is  to  become  a  man  has  an 
organization  of  its  own,  we  are  most  assuredly  unable  to  find  in 
it  any  traces  of  the  organization  of  a  man.  Another  character- 
istic is  that,  so  far  as  we  know,  it  has  been  handed  down,  in  an 
unbroken  line  of  continuity,  for  many  million  years,  from  the 
oldest  living  things,  generation  after  generation,  to  the  modern 
forms  of  life,  so  that  it  has  leavened  the  whole  lump  of  living 
matter. 

While  we  know  nothing  of  its  origin,  and  while  we  must  guard 
ourselves  from  all  unproved  assumptions,  there  seem,  from  our 
present  standpoint,  to  be  insuperable  objections  to  the  view  that 
this  influence  is  either  matter  or  energy.  While  we  know  it  only 
in  union  with  protoplasm,  it  would  seem  that,  if  it  is  matter,  it  must 
long  ago  have  reached  the  minimum  divisibile.  If  it  is  physical 
energy,  or  wave  motion,  or  perigenesis  of  plastidules,  it  is  hard  to 
understand  why  it  has  not  all  been  dissipated  long  ago,  or  how  it 
can  multiply  itself. 

We  know  that  it  is,  and  this  is  in  itself  a  fact  of  the  utmost 
moment,  even  if  we  are  never  to  find  out  what  it  is.  We  are  told 
that  belief  that  it  has  at  some  time  arisen  from  the  properties  of 
inorganic  matter  is  a  logical  necessity,  but  the  only  logical  necessity 
is  that  where  knowledge  ends  we  should  admit  ignorance. 

Honesty  of  purpose  and  expediency  unite  in  the  demand  that 
we  build  biology  upon   a  foundation  which  can  never  be  shaken; 


282  THE  FOUND ATIOIVS  OF  ZOOLOGY 

and  if  our  creed  is  a  humble  confession  that  while  we  do  not  know 
whether  life  is  independent  of  matter  or  not,  —  that  v\hile  we  do  not 
know  what  the  relation  between  mind  and  matter  is,  we  should  like 
to  find  out,  — we  need  fear  no  attack  by  anything  in  the  universe  or 
outside  it. 

This  being  the  case,  the  discovery  of  natural  selection  may 
seem  to  some  to  have  no  bearing,  either  positively  or  negatively, 
upon  the  argument  from  contrivance  ;  since  the  words  "  survival  of 
the  fittest"  are  meaningless  unless  the  being  which  remains  fit  after 
the  selective  process  has  acted  is  the  same  as  the  one  on  which  it 
acted. 

I  am  not  able  to  share  this  opinion  ;  for  while  natural  selection, 
inasmuch  as  it  presupposes  personal  identity,  may  be  only  an  im- 
perfect explanation  of  life,  it  still  remains  a  strictly  scientific  ex- 
planation of  one  great  biological  problem,  the  origin  of  species, 
revealing  to  us  the  "  physical  causation "  of  the  division  of  the 
living  world  into  more  or  less  isolated  species,  characterized  by 
fitness  for  that  part  of  the  order  of  nature  which  makes  up  the 
environment  of  each. 

Aristotle  believed  that  all  living  things,  man  included,  are 
generated  out  of  dead  matter ;  and  it  seems  clear  that,  before 
natural  selection  was  discovered,  we  should  have  been  warranted 
in  demanding  proof  of  Aristotle's  view  before  admitting  that  living 
beings  are  inorganic  in  origin ;  but,  nowadays,  no  one  can  logically 
demand  that  some  one  shall  make  out  of  dead  matter  a  living  human 
being,  with  a  human  mind,  like  the  golden  statues  which  Homer 
attributes  to  the  skill  of  Vulcan,  before  he  will  make  this  admission. 

Whether  the  production  of  a  living  man  by  physico-chemical 
methods  be  absolutely  impossible  or  not,  all  admit  that  it  is  practi- 
cally impossible;  although  few  will  assert  with  the  same  confi- 
dence that  it  is  impossible  to  make  in  this  way  a  being  sufficiently 
like  some  living  things  to  create  a  reasonable  expectation  that 
its  history  will  be,  in  all  essential  particulars,  like  the  history  of 
life  as  we  actually  know  it.  If  any  are  bold  enough  to  make  this 
assertion,  their  frame  of  mind  seems  to  me  to  be  highly  injudicious 
in  the  present  condition  and  present  prospects  of  science ;  for 
the  progress  of  knowledge  may  at  any  time  compel  them  to 
abandon  it. 


PALEV,   AND    THE  ARGUMENT  FROM  CONTRIVANCE      283 

While  I  am  unable  to  agree  with  Huxley  that  natural  selection 
has  given  the  death-blow  to  the  belief  that  the  contrivances  of 
human  artificers  prove  that  nature  is  a  contrivance  and  the  work 
of  an  artificer,  it  has,  in  my  opinion,  so  greatly  weakened  the  value 
of  the  evidence  for  this  belief  that  no  one  can  safely  hold  that  it 
is  conclusive. 

Now,  no  one  who  is  trained  in  the  methods  of  science  can  find 
in  an  inconclusive  argument  any  legitimate  basis  for  any  other 
state  of  mind  than  a  suspension  of  judgment  and  a  desire  for 
more  evidence ;  for  all  must  hold  it  unwise  and  precarious  to  base 
a  positive  opinion  on  absence  of  disproof. 

The  hardest  of  intellectual  virtues  is  philosophic  doubt,  and 
the  mental  vice  to  which  we  are  most  prone  is  our  tendency  to 
believe  that  lack  of  evidence  for  an  opinion  is  a  reason  for  believing 
something  else.  This  tendency  has  value  in  practical  matters  which 
call  for  action,  but  the  man  of  science  need  neither  starve  nor 
choose.  Suspended  judgment  is  the  greatest  triumph  of  intellectual 
discipline,  and  while  vacillation  brands  the  man  of  affairs  with 
weakness,  no  opinion  on  philosophical  matters  has  any  value  unless 
it  meets  all  possible  contingencies. 

I  am  neither  a  materialist  nor  a  monist ;  and  yet  I  think  it  wise, 
to  ask  what  would  be  the  significance  of  the  production  of  a  living 
being  by  physico-chemical  methods ;  and  this  I  shall  try  to  do  in 
the  next  lecture ;  for  even  if  living  beings  and  their  ways  and  works 
were  shown  to  afford  no  peculiar  evidence  of  purpose  or  intention, 
this  would  not  be  proof  that  there  is  no  such  evidence  in  nature  ; 
for  it  may  be  that  all  nature,  inorganic  and  organic  alike,  affords 
equal  evidence  of   purpose  or  intention. 


LECTURE    XII 

THE   MECHANISM    OF   NATURE 


"  Ideas  which  are  observed  to  be  connected  together  are  vulgarly  considered  under  the 
relation  of  cause  and  effect,  whereas,  in  strict  and  philosophic  truth,  they  are  only  related  as 
the  sign  and  the  thing  signified."  —  Berkeley,  "The  Theory  of  Vision  Vindicated  and 
Explained"  (13). 


LECTURE   XII 

THE  MECHANISM  OF  NATURE 

In  this  lecture  I  shall  review  the  evidence  that  has  convinced 
many  thoughtful  men  that  natural  knowledge  is  no  more  than 
knowledge  of  order.  My  reason  for  asking  you  to  go  with  me 
over  ground  which  is  already  familiar  is  this :  I  wish  you  to  ask 
yourselves,  as  we  make  our  review,  if  it  is  not  obvious  that  the 
discovery  that  nature  is  orderly  can  throw  no  light  on  the  origin 
of  anything  in  nature.  Order  is  not  an  explanation  of  anything ; 
but  something  that  itself  calls  for  explanation. 

It  must  not  be  supposed  that  no  "philosopher"  has  attempted 
to  account  for  order  in  nature;  for  many  hold  this  a  simple  mat- 
ter, easy  to  understand,  although  their  reasoning  may  turn  out, 
when  examined,  to  be  no  more  than  an  assertion  that  nature  is 
orderly  because  there  is  order  in  nature. 

Some  tell  us,  for  example,  that  the  order  we  discover  in  nature 
is  a  necessary  result  of  the  conservation  of  energy.  Like  causes 
must  be  followed  by  like  effects,  they  tell  us,  unless  force  has 
in  the  meantime  come  into  existence  or  gone  out  of  existence; 
and  this  cannot  be  the  case  if  force  is  persistent.  As  proof  that 
force  is  persistent  we  are  told  that  like  effects  do  follow  like 
causes,  or,  in  other  words,  that  nature  is  orderly. 

Some  students  of  zoology  go  one  step  deeper  into  the  heart 
of  the  matter,  and  tell  us  that  our  minds  are  unable  to  conceive 
the  production  or  the  destruction  of  energy,  because  the  whole 
history  of  life  has  been  a  history  of  response  to  causation,  and 
because  all  living  things  that  did  not  thus  respond  have  been 
exterminated  in  the  struggle  for  existence,  and  because,  for  this 
reason,  our  confidence  in  the  order  of  nature  is  no  more  than 
our   history  would   lead   one   to    expect;    although   it   seems    plain 

287 


288  THE  FOUNDATIONS  OF  ZOOLOGY 

that  our  only  reason  for  believing  that  the  thing  which  we 
expect  will  be  the  thing  which  comes  about  is  our  confidence  that 
nature  is  orderly ;  and  that  this  way  of  accounting  for  order  in 
nature  brings  us  at  last  to  the  very  point  from  which  we  set 
out. 

Of  all  the  strange  errors  that  vex  the  mind  of  man,  one  of 
the  strangest  is  the  opinion  that  our  faculties  would  lose  their 
reality  and  their  value  if  the  history  of  man  were  proved  to  be 
orderly,  and  what  might  reasonably  have  been  expected,  for  that 
our  history  cannot  have  the  slightest  bearing  on  the  reality  of 
anything  in  our  nature  seems  so  obvious  that  it  is  hard  to  see 
why  any  one  should  question  it. 

If  one  knows  that  he  is  refreshed  by  food  and  drink,  I  fail  to 
see  what  bearing  on  this  conviction  any  amount  of  anatomical 
or  physiological  or  historical  acquaintance  with  his  digestive 
organs  can  have,  even  if  it  should  enable  him  to  deduce  these 
organs  from  physics  and  chemistry  or  to  make  others  like  them. 

Scientific  knowledge  of  digestion  gives  valuable  information 
as  to  the  conditions  under  which  food  and  drink  are  beneficial, 
and  it  helps  us  to  regulate  our  natural  appetites  and  to  avoid 
errors  and  excesses ;  but  no  one  ever  dreams  that  this  is  evidence 
that  these  appetites  are  not  real. 

You  may  perhaps  find  some  reason  to  doubt  whether  you 
see  me  in  this  room  or  hear  this  lecture ;  for  all  I  know,  you  may 
find  still  more  reason  to  doubt  whether  you  profit  by  so  doing; 
but  can  you  doubt  that  you  see  and  hear,  or  that  on  the  whole 
you  profit  by  seeing  and  hearing .''  Would  you  not  be  just  as 
sure  even  if  you  knew  nothing  of  optics  or  acoustics  or  even  of 
eyes  or  ears  ?  For  my  own  part  I  should  be  as  sure  I  see 
and  hear,  and  see  and  hear  to  my  advantage,  as  I  am  now,  even 
if  my  days  were  passed  in  a  laboratory  for  the  manufacture  of 
seeing  and  hearing  beings.  Since  my  reason  began  to  make 
itself  known  to  me  before  I  knew  I  had  a  brain,  my  conviction 
that  I  am  a  rational  being,  like  my  conviction  that  it  is  good  to 
be  a  rational  being,  is  independent  of  knowledge  of  the  existence 
of  my  brain.  Since  my  power  to  draw  inferences  from  the  data 
of  sense  and  to  profit  by  them  is  independent  of  acquaintance 
with   the    mechanism    of   my  brain,   I   fail   to  see  why  my  reason 


THE  MECHAmSM  OF  NATURE  289 

should  be  any  the  less  real  or  any  the  less  valuable  even  if  a  skil- 
ful physiologist  should  some  time  succeed  in  imitating  all  the 
manifestations  of  rational  life  by  playing  on  a  human  brain  with 
electrodes. 

Knowledge  of  nature  corrects  our  judgment  by  showing  us 
the  conditions  under  which  it  is  trustworthy,  and  by  revealing 
errors  which  rest  upon  imperfect  experience ;  but  I  cannot  con- 
ceive how  any  one  should  suppose  that  this  fact  has  any  bearing 
upon  the  reality  or  the  value  of  reason. 

Centuries  of  discussion  warn  us  that  the  establishment  of 
mechanical  explanations  of  the  phenomena  of  human  life  would, 
in  the  opinion  of  many,  destroy  volition,  and  right  and  wrong, 
and  duty,  and  moral  responsibility ;  and  while  I  do  not  suppose 
my  own  inability  to  see  why  any  of  these  dreadful  things  should 
happen  will  count  for  much,  this  inability  is  real. 

So  far  as  I  can  see,  the  reduction  of  all  nature  to  mechanical 
principles  would  m'ean  nothing  more  than  that  all  the  phenomena 
of  nature  are  orderly  and  such  as  might  have  been  expected ; 
and  I  am  quite  unable  to  discover  what  bearing  the  fact  that 
an  event  may  be  counted  on  with  confidence  has  on  the  ques- 
tion whether  it  is  "necessary"  or  "spontaneous,"  for  the  dis- 
covery that  phenomena  are  orderly  tells  us  nothing  about  their 
origin. 

I  cannot  see,  for  example,  how  the  man  who  is  unstable  in 
all  his  ways  furnishes  any  better  evidence  of  freedom  than  the 
man  who  may  be  counted  on  with  confidence;  nor  can  I  see 
how  the  vagaries  of  a  lunatic  give  better  proof  of  moral  accounta- 
bility than  the  actions  of  the  man  who  does  what  all  his  fellow- 
men  expect  from  him. 

In  a  word,  I  do  not  see  why  the  ultimate  establishment  of  a 
mechanical  explanation  of  all  the  phenomena  of  nature  should 
destroy  or  set  aside  any  one  thing  we  know  now. 

"The  notions  of  guilt  and  merit,  justice  and  reward,  are  in 
the  minds  of  men  antecedent  to  all  metaphysical  disquisitions; 
and  according  to  these  received  notions,  it  is  not  doubted  that 
man  is  accountable." 

Huxley,  who  like  Sir  Isaac    Newton  tells   us   that    he   lives    in 
the  hope  that  all  the  phenomena    of    nature    will    be    reduced    to 
u 


290  THE  FOUNDATIONS  OF  ZOOLOGY 

mechanical  principles,  also  tells  us  ("  Physical  Basis  of  Life,"  1868), 
that  a  wise  man  must  be  fully  possessed  of  two  beliefs :  "  The 
first,  that  the  order  of  nature  is  ascertainable  by  our  faculties  to 
an  extent  which  is  practically  unlimited ;  the  second,  that  our 
volition  counts  for  something  as  a  condition  of  the  course  of 
events." 

Again,  twenty-five  years  later  (1893),  he  says  ("Evolution  and 
Ethics")  that  fragile  reed  as  man  may  be,  "there  lies  within 
him  a  fund  of  energy,  operating  intelligently,  and  so  far  akin  to 
that  which  pervades  the  universe,  that  it  is  competent  to  influence 
and  modify  the  cosmic  process." 

While  I  see  no  reason  why  every  living  thing  may  not  contain 
some  small  part  of  this  influence  which  counts  foj  something  as 
a  condition  of  the  course  of  events,  I  am  unable  to  see  how  or 
where  this  assertion  is  irreconcilable  with  the  admission  that,  for 
all  one  knows  to  the  contrary,  all  nature  may  ultimately  prove 
mechanical. 

If  I  admit  my  accountability,  if  I  have  every  reason  to 
believe,  and  no  reason  to  doubt,  that  my  volition  will  count,  how 
can  proof  that  I  do  nothing  which  might  not  have  been  expected 
show  that  my  confidence  is  deceptive  .'' 

"  If  it  is  foreseen  that  such  an  action  shall  be  done,  may  it 
not,"  asks  Berkeley,  "  also  be  foreseen  that  it  shall  be  an  effect 
of  human  choice  and  liberty }  To  me,  certain  and  necessary 
seem  very  different ;  there  being  nothing  in  the  former  notion 
that  implies  restraint,  nor  consequently  which  may  not  consist 
with  a  man's  being  accountable  for  his  actions.  And  though  by 
abstract  reasoning  you  would  puzzle  me,  and  seem  to  prove  the 
contrary,  this  inward  evidence  of  plain  fact  will  bear  me  up 
against  all  your  reasonings,  however  subtle  and  refined." 

Even  if  one  doubt  whether  volition  be  a  good  thing,  whether 
ability  to  do  wrong  may  not  outweigh  the  ability  to  do  right, 
how  does  this  disprove  responsibility  .''  If  what  I  will  come  about 
as  I  expect,  I  am  responsible  ;  whether  the  "  causa  causarnm,"  or 
"  I,"  or  "  physical  causation,"  be  the  cause  of  the  effect ;  or  even 
if  I  know  nothing  of  absolute  or  efficient  causation. 

The  answer  I  give  to  the  question  whether  my  volition  be 
within  or  without  the  chain  of  physical  causation,  has    nothing   to 


THE  MECHANISM  OF  NATURE 


291 


do  with  the  reality  of  my  freedom;  for  one  who  knows  nothing, 
either  positively  or  negatively,  about  absolute  freedom  may  never- 
theless be  convinced  that,  as  a  practical  matter,  he  is  free  and 
responsible. 

While  we  may  from  premises  infer  a  conclusion,  it  will  not  fol- 
low that  we  can  argue  reciprocally  and  from  the  conclusion  infer 
the  premises. 

Proof  that  my  voluntary  acts  are  arbitrary  and  not  mechanical 
might  prove  them  free ;  but  it  does  not  follow  that  my  confidence 
in  my  freedom  proves  that  it  is  arbitrary  and  not  mechanical;  for 
if  mechanical  means  orderly,  the  only  contrasted  meaning  I  can  find 
for  the  word  arbitrary  is  disorderly. 

When  we  speak  of  the  reduction  of  nature  to  mechanical  princi- 
ples, and  when  v/e  compare  the  works  of  nature  to  a  machine,  what 
do  these  words  mean } 

Our  notion  of  the  human  contrivances  we  call  machines  is  clear 
and  definite.  A  clock  is  a  machine,  and  so  is  a  steam-engine.  The 
definition  of  machines  in  the  "  Encyclopaedia  Britannica  "  tells  us 
they  "  produce  some  useful  purpose,"  and  use  is  the  very  essence 
of  an  artificial  machine;  for  mechanical  toys  are  not  made  without 
a  purpose.  In  common  speech  a  purposeless  machine  is,  so  far  as 
may  be,  a  contradiction  in  terms;  and  they  who  find  difficulty  in 
reconciling  the  mechanism  of  nature,  or  the  mechanism  of  our 
minds,  with  purpose  or  intention  must  have  some  other  meaning  in 
mind.  To  put  ourselves  in  their  place,  we  must  try  to  find  out  this 
meaning  if  we  can,  for  it  may  be  that  the  assertion  that  our  minds 
are  mechanical  will  prove  to  be  only  another  way  of  saying  that  they 
are  useful. 

Mechanics  divide  artificial  implements  into  instruments,  struct- 
ures, and  machines.  Clocks  and  locomotives  are  machines;  railroads 
and  bridges  are  structures;  and  the  wrenches  and  files  of  the  engi- 
neer are  instruments.  While  these  three  classes  are  not  sharply 
separated,  I  think  they  bring  out  the  meaning  we  are  seeking. 
Machines,  instruments,  and  structures  are  alike  useful,  but  they 
are  not  used  in  the  same  way.  What  the  wrench  and  the  bridge 
were  before  they  were  used,  that  they  remain  while  used  and  after 
they  have  been  used,  and  they  are  used  only  so  long  as  they  are 


292  THE  FOUNDATIONS   OF  ZOOLOGY 

actively  employed  by  a  user;  but  a  clock  wound  up  and  started  is 
different  from  a  clock  run  down,  and  so  long  as  its  pendulum  swings 
it  counts  the  passing  seconds  and  tells  the  flight  of  time  whether  we 
use  it  or  not.  Once  set  agoing,  it  is  independent  of  a  user,  and  it 
does  its  work  "by  itself"  until  it  comes  to  rest;  although  its  inde- 
pendence of  a  user  does  not  imply  that  it  is  useless,  for  so  long  as 
it  runs  any  one  may  use  it  who  knows  how.  If  it  were  kept  wound 
up  by  a  wheel  under  a  waterfall,  it  would  be  part  of  the  mechanism 
of  nature;  and,  once  started,  it  would,  barring  accidents,  be  inde- 
pendent of  human  users.  When  the  mechanism  of  nature  is  com- 
pared to  human  machines,  these  often  seem  to  be  thought  of  in  this 
way,  as  contrasted  with  instruments  and  structures.  Attention  is 
thus  concentrated  on  their  distinctive  or  specific  characteristic,  to 
the  temporary  neglect  of  that  usefulness  which  is  the  common  or 
generic  characteristic  of  all  artificial  implements. 

Water  falls  by  gravitation  and,  winding  up  the  weights,  which 
also  fall  by  gravitation,  keeps  in  motion  the  pendulum  which,  so 
long  as  it  moves,  beats  seconds  by  gravitation.  As  gravitation  is 
said  to  be  mechanical  and  "  universal,"  it  has  seemed  to  some  that 
the  clock  thus  placed  must  go  on  recording  the  flight  of  time,  since 
it  is  part  of  the  mechanism  of  nature,  and  is  independent  of  human 
support  or  intervention.  In  other  words,  the  automatism  of  the 
clock  —  that  is,  its  independence  of  human  users  —  is  held  to  show 
that  it  is  self-sustaining;  but  they  who  infer  from  this  analogy  that 
the  mechanism  of  nature  is  self-sustaining,  while  they  deny  that  the 
analogy  shows  that  this  mechanism  has  a  purpose,  seem  to  me  to 
play  fast  and  loose  with  the  analogy,  and  to  reason  like  the  dema- 
gogue who  tells  the  workman  cheap  money  will  raise  his  wages,  and 
bring  down  the  price  of  those  products  of  labor  for  which  he  spends 
his  wages. 

Must  we  not  ask  what  we  mean  by  the  assertion  that,  once 
started,  the  movement  of  the  clock  is  automatic .''  What  does  the 
word  automatic  mean  in  this  connection.?  One  thing  it  clearly 
means:  that  the  movement  is  independent  of  human  users.  It  also 
means  that,  the  conditions  being  given,  its  movements  may  be 
counted  on  with  confidence.  What  else  does  it  mean?  Do  we 
find,  in  the  clock  or  anywhere  else,  any  ground  for  the  belief  that 
its  automatic  movements,  once  started,  are  necessary  or  self-sustain- 


THE  MECHANISM  OF  NATURE  293 

ing?  Or  do  we  find  any  reason  to  think  that  its  independence  of 
a  user  has  any  bearing  on  its  usefulness  to  those  who  know  how 
to  use  it?  As  it  is  obvious  that  the  clock  will  not  go  unless  the 
water  continues  to  run  down  hill,  the  assertion  that  it  is  self- 
sustaining  clearly  has  no  better  basis  than  our  confidence  that  water 
which  is  free  to  run  dov/n  hill  will  do  so;  but  this  basis  is  so  firm 
that  I  do  not  suppose  any  one  looks  for  or  holds  that  he  has  any 
other. 

Water  runs  down  hill  by  gravitation ;  and  the  predictions  we 
base  on  the  stability  of  gravitation  command  our  utmost  confi- 
dence. The  nautical  almanac,  published  several  years  in  advance, 
gives  the  predicted  places  of  the  sun,  moon,  and  principal  planets 
from  day  to  day,  and  in  some  cases,  from  hour  to  hour,  through 
the  whole  year.  Unless  gravitation  is  stable,  these  predictions  are 
worthless ;  yet  no  one  hesitates  to  trust  his  fortune  and  his  life 
and  even  the  safety  and  honor  of  his  country  to  the  nautical 
almanac.  Even  if  this  prove  at  fault,  if,  in  any  particular,  obser- 
vation fail  to  verify  its  predictions,  no  one  ever  dreams  that  its 
principles  are  wrong.  On  the  contrary,  the  astronomer  himself, 
after  making  sure  that  computers  and  printers  and  those  who  use 
the  predictions  have  made  no  mistake,  uses  this  failure  to  correct 
his  estimates  of  the  sizes  and  distances  and  velocities  of  the 
heavenly  bodies.  Unknown  planets  and  satellites,  worlds  which 
no  human  eye  had  seen,  have  been  deduced  from  the  data  of 
astronomy  with  such  exactness  that  the  new  world  has  been  found 
when  the  telescope  has  been  turned  to  the  designated  spot. 

When  we  reflect  upon  the  meaning  of  our  confidence  in  gravi- 
tation, who  can  wonder  if  some  think  that  the  clock  which  is 
found  to  fall  into  a  place  in  the  same  system  with  the  facts  of 
astronomy  must  go  on  of  necessity^  although  no  words  can  be  more 
emphatic  than  those  in  which  the  men  of  science  repudiate  this 
belief  .?  Huxley,  for  example,  "  anathematizes  "  it  in  the  following 
words,  to  which  all  thoughtful  men  of   science  must  subscribe  :  — 

"What  is  the  dire  necessity  and  'iron'  law  under  which  men 
groan  ?  Truly,  most  gratuitously  invented  bugbears.  I  suppose 
that  if  there  be  an  iron  law,  it  is  that  of  gravitation,  and  if  there 
be  a  physical  necessity,  it  is  that  a  stone,  unsupported,  must  fall 
to   the  ground.     But  what  is  all  we  really  know   about  the  latter 


294  THE  FOUNDATIONS   OF  ZOOLOGY 

phenomenon  ?  Simply  that  in  all  human  experience  all  stones 
have  fallen  to  the  ground  under  these  conditions,  and  that  we 
have  not  the  smallest  reason  for  believing  that  any  stone  so  cir- 
cumstanced will  not  fall  to  the  ground,  and  that  we  have,  on  the 
contrary,  every  reason  to  believe  that  it  will  so  fall.  It  is  very 
convenient  to  indicate  that  all  the  conditions  of  belief  have  been 
fulfilled  in  this  case,  by  calling  the  statement  that  the  unsup- 
ported stone  will  fall  to  the  ground  a  law  of  nature.  But  when, 
as  commonly  happens,  we  change  will  into  must,  we  introduce  an 
idea  of  necessity  which  most  assuredly  does  not  lie  in  the  observed 
facts,  and  has  no  warranty  that  I  can  discover  elsewhere.  For 
my  part  I  utterly  repudiate  and  anathematize  the  intruder.  Fact 
I  know ;  and  Law  I  know ;  but  what  is  this  Necessity  save  an 
empty  shadow  of  my  own  mind's  throwing  ?  "  ^ 

"Attraction,"  says  Berkeley,  "cannot  produce,  and  in  that 
sense  account  for  the  phenomena,  being  itself  one  of  the  phenom- 
ena produced  and  to  be  accounted  for." 

If  words  like  these  mean  anything,  they  mean  that  they  who 
think  the  movements  of  the  mechanism  of  nature  necessary  utterly 
misapprehend  the  value  and  significance  of  natural  knowledge. 
They  mean  that  belief  that  the  automatic  clock  is  self-sustaining 
and  must  go  finds  no  support  in  the  teachings  of  science ;  except 
so  far  as  it  may  be  supported  by  something  in  our  own  nature. 

If  man  were  a  pure  intellect,  the  intensity  of  our  confidence 
in  gravitation  might  be  identical  with  its  logical  value ;  but  as  a 
man  is  a  ponderable  body  and  not  a  pure  intellect,  serious  bodily 
harm,  or  even  death,  may  follow  failure  to  respond  to  that  part  of 
the  order  of  nature  which  we  formulate  as  the  law  of  gravitation. 

The  actions  of  most  terrestrial  animals  large  enough  to  be 
injured  by  a  fall  are  so  adjusted  to  this  order  that  the  practical 
value  of  their  responses  does  not  bear  any  exact  relation  to  their 
opportunities  for  acquiring  experience.  When  a  mud-turtle  or  a 
marine  crab  is  put  on  a  table,  it  may  walk  over  the  edge  without 
hesitation ;  but  a  land-crab,  on  reaching  the  edge,  hunts  for  a  safe 
place  to  climb  down,  and  if  forced  to  go  over,  clings  to  the  table, 
or    else    drops    with    caution    after    preparation.     Nestling    birds, 

1"  Physical  Basis  of  Life,"    1868. 


THE  MECHANISM   OF  NATURE  295 

before  they  learn  to  fly,  climb  on  to  the  edge  of  the  nest,  but  they 
seldom  tumble ;  and  they  will  cling  to  the  finger,  when  this  is 
inclined,  in  such  a  way  as  to  keep  their  balance.  They  who 
believe  instinct  is  inherited  knowledge  may  say  the  land-crab  knoivs 
the  danger  of  a  fall  by  instinct ;  and  they  may  be  disposed  to 
think  that  the  intellectual  value  of  our  confidence  in  gravitation 
is  in  part  innate  and  independent  of  experience. 

A  single  hard  tumble  may  do  more  to  convince  a  child  that 
unsupported  bodies  will  fall  than  long  impersonal  experience ;  and 
the  intensity  of  any  conviction  which  is  consistent  with  our  natu- 
ral adjustments  cannot  be  measured  by  the  amount  of  experience, 
although  this  is  the  only  measure  of  its  value  as  knowledge,  for 
we  have  no  other  way  to  learn  when  and  how  far  an  adjustment 
is  judicious,  and  when  it  is  not,  than  through  experience  of  the 
order  of  nature.  The  question  we  now  seek  to  answer  is  not 
how  strong  our  confidence  in  gravitation  is,  but  what  it  is  worth, 
and  we  find  that  its  value  as  knowledge  may  be  measured,  quan- 
titatively as  well  as  qualitatively,  by  human  experience,  and  that 
it  has  no  inherent  or  a  priori  intellectual  value ;  although  the 
practical  value,  in  preserving  life,  of  the  responses  of  living  things 
to  the  stimulus  of  gravitation  is  often  independent  of  experience ; 
and  although  we  may,  in  these  cases,  be  quite  unable  to  tell 
whether  these  responses  are  accompanied  by  mind  or  not. 

Ignorance  is  not  knowledge,  as  we  use  words ;  and  one  school 
of  "  philosophers "  seems  to  me  to  have  brought  needless  confu- 
sion into  the  discussion  of  the  nature  and  sources  of  human 
knowledge  by  failure  to  distinguish  the  practical  value  to  living 
things  of  response  to  the  order  of  nature  from  the  logical  value 
of  our  own  conscious  intelligent  confidence  in  the  stability  of  this 
order;  for  whether  these  things  are  fundamentally  different  or 
not,  they  are  practically  different  for  us. 

In  another  school  of  "philosophers,"  who  teach  that  our  minds 
would  lose  their  value  unless  we  have  a  monopoly  of  reason, 
equal  confusion  seems  to  me  to  follow  failure  to  perceive  that 
every  responsive  action  in  nature  may,  for  all  we  know  to  the 
contrary,  be  accompanied  by  some  small  part  of  that  which  we 
call  mind. 

If   our   scientific   creed   is   a   modest    confession   that  while  we 


296  THE  FOUNDATIONS  OF  ZOOLOGY 

do  not  know  what  the  relation  between  mind  and  matter  is,  we 
should  like  to  find  out,  the  controversies  between  the  realists  and 
the  idealists  and  the  monists  and  the  evolutionists  and  the  materi- 
alists will  concern  us  as  little  as  a  summer  shower  concerns  a 
duck. 

Our  knowledge  of  the  stability  of  gravitation  is  accompanied 
by  an  innate  or  natural  tendency  to  respond  to  it  as  a  stimulus, 
—  a  tendency  which  we  share  with  most  terrestrial  animals  and 
plants,  —  and  all  knowledge  is  no  doubt  accompanied  by  similar 
emotional  elements ;  nor  does  it  seem  possible  to  discover  any 
sharp  line  between  the  responses  which  living  things  make  by 
nature  and  prior  to  experience  and  our  own  conscious,  rational 
adjustments;  although  the  response  of  a  germinating  seed  to 
gravitation  and  our  own  acquaintance  with  Newton's  laws  are 
things  so  different  that  it  would  do  violence  to  the  usage  of  com- 
mon speech  to  call  them  both  knowledge. 

If  we  analyze  in  the  same  way  the  scientific  or  objective  value 
of  our  confidence  in  the  stability  of  the  matter  of  the  clock,  of 
the  iron  and  the  brass,  and  the  wheels  and  bearings  and  pinions, 
we  find  that  this,  like  our  confidence  that  its  movements  will  be 
orderly,  is  reasonable  and  judicious,  but  not  necessary  or  absolute. 

We  are  led  back,  step  by  step,  to  the  law  of  the  indestructi- 
bility of  matter,  just  as  we  are  led,  by  the  study  of  gravitation 
and  similar  phenomena,  to  the  law  of  the  conservation  of  energy ; 
and  finally  we  may  perhaps  be  led  to  regard  these  laws  as  illus- 
trations of  a  still  more  general  mechanical  principle, — the  continu- 
ity of  motion  ;  but  those  men  of  science  who  see  most  reason  to 
believe  that  all  the  phenomena  of  nature  are  phenomena  of  motion, 
reducible  to  mechanical  principles,  are  the  ones  who  are  most 
emphatic  in  their  assertion  that,  while  it  is  folly  to  dispute  these 
principles,  they  know  no  evidence  that  they  are  necessary  or 
absolute.  Our  confidence  in  them  is  reasonable  and  judicious ; 
but  we  know  no  reason  why  they  must  hold  good. 

"All  the  phenomena  in  nature,"  says  Berkeley,  "are  produced 
by  motion.  Mechanical  laws  of  nature  or  motion  direct  us  how 
to  act,  and  teach  us  what  to  expect.  Nor  are  we  concerned  at 
all    about    the    forces,    neither    can   we    know   or    measure    them, 


THE  MECHANISM  OF  NATURE  297 

Otherwise  than  by  their  effects,  that  is  to  say,  the  motions;  which 
motions,  only,  and  not  the  forces,  are  indeed  in  the  bodies. 
Bodies  are  moved  to  and  from  each  other,  and  this  is  performed 
according  to  different  laws.  The  natural  or  mechanical  philoso- 
pher endeavors  to  discover  these  laws  by  experiment  and  reason- 
ing. But  what  is  said  of  forces  residing  in  bodies,  whether 
attracting  or  repelling,  is  to  be  regarded  only  as  a  mathematical 
hypothesis,  and  not  as  anything  really  residing  in  nature."  ^ 

Of  Newton's  laws,  we  are  told  in  the  "Encyclopaedia  Britannica," 
article  Mechanics,  "These  laws  are  to  be  considered  as  deductions 
from  observation  and  experiment,  and  in  no  sense  as  having  any 
a  priori  foundation." 

Jevons  tells  us  ("  Principles  of  Science,"  p.  739):  "I  demur  to 
the  assumption  that  there  is  any  necessary  truth  even  in  such 
fundamental  laws  of  nature  as  the  Indestructibility  of  Matter,  the 
Conservation  of  Energy,  or  the  Laws  of  Motion.  With  the 
statement  of  every  law  we  ought  properly  to  join  an  estimate  of 
the  number  of  instances  in  which  it  has  been  observed  to  hold 
good,  and  the  probability  {i.e.  the  reasonableness  of  the  expecta- 
tion] thence  calculated,  that  it  will  hold  true  in  the  next  case. 
No  finite  number  of  instances  can  warrant  us  in  expecting  with 
certainty  that  the  next  event  will  be  of  like  nature." 

Many  who  admit  that  since  our  knowledge  of  matter  and 
motion  is  based  on  observation  and  experiment  it  has  no  more 
value  than  experience  gives,  hold,  nevertheless,  that  there  are 
certain  necessary  truths  or  axioms ;  although  the  word  axiom  does 
not  by  derivation  mean  a  necessary  truth,  but  one  that  is  worthy 
of  confidence.  So  far  as  nature  is  believed  to  give  evidence  of  a 
necessary  law  of  causation,  this  opinion  may  be  properly  consid- 
ered here,  and  we  must  ask  what  we  mean  by  the  assertion  that 
this  law  is  necessary.  Philosophers  may,  if  they  see  fit,  define 
cause  as  "that  which  produceth  a  thing  and  maketh  it  to  be  what 
it  is "  ;  but  it  is  one  thing  to  define  a  word,  and  quite  another 
to  find  in  nature  any  corresponding  reality.  The  discovery  of  a 
definition  of  "Mermaid"  in  the  dictionary  is  no  evidence  that  mer- 
maids  exist   in   nature;     although    it   may   be   evidence   that  they 

1  "  Siris,"  234. 


298  THE  FOUNDATIONS  OF  ZOOLOGY 

exist,  or  have  existed,  in  human  minds ;  nor  is  proof  that  a  thing 
exists  in  all  human  minds  proof  that  it  exists  in  nature  outside 
human  minds. 

The  "  law  of  causation "  seems  to  consist  of  two  elements. 
Our  whole  history  as  living  beings  gives  new  strength  continually 
to  our  confidence  that,  when  event  A,  which  we  call  a  cause, 
exists,  event  B,  which  we  call  its  effect,  may  be  expected ;  and 
that  in  the  absence  of  A,  B  will  not  be  found.  The  belief  also 
prevails  that  B  cannot  occur  without  A,  and  that  it  must  occur 
with  A. 

It  does  not  seem  difficult  to  consider  these  elements  separately; 
and  whatever  may  be  our  opinion  of  their  separation  in  fact,  the 
analysis  may  help  us  to  examine  the  subject. 

Every  rational  action  is  based  upon  our  confidence  that  each 
event  is,  in  course  of  nature,  a  sign  of  others  that  may  be  ex- 
pected. This  confidence  gathers  strength  with  every  moment  of 
our  lives,  and  is  so  ingrained  in  our  language,  that  we  speak  of 
the  sign  as  if  it  were,  in  very  truth,  the  thing  signified.  When 
we  hear  a  pattering  sound  on  the  roof,  we  do  not  restrict  our- 
selves to  fact,  and  say  we  hear  a  sound.  We  say  we  hear  it 
rain.  I  have  tried  to  show  that  life  itself,  not  only^  the  conscious, 
rational  life  of  man  and  of  the  higher  animals,  but  the  life  of 
every  animal  and  every  plant,  is  response.  A  living  being  is  a 
being  which  when  affected  by  A  makes  preparations  to  meet  B. 
The  rhizopod  which  flows  around  and  ingests  small  particles  of 
food,  while  it  retracts  its  pseudopodia  when  violently  jarred,  re- 
sponds to  the  law  of  causation  as  much  as  the  sailor  who  corrects 
his  chronometer  by  observations  on  the  satellites  of  Jupiter.  Re- 
sponse to  this  law  is  admitted  to  be  entirely  organic  in  the  lower 
living  things,  and  to  a  great  extent  organic  in  all.  As  man  has 
by  nature  structural  adjustments  to  many  of  these  relations  be- 
tween phenomena,  the  law  of  causation  seems,  to  this  extent, 
embodied  in  his  organization  as  part  of  his  nature,  and  we  have 
already  seen  that,  while  the  value  of  our  confidence  in.  this  order 
is  measured  by  our  experience,  its  intensity  is  not.  There  is  no 
constant  ratio  between  the  intensity  with  which  a  burnt  child 
dreads  the  fire  and  the  number  of  times  it  has  been  burned.  In 
this  sense  the  law  of   causation  seems   to    be    necessary,  inasmuch 


THE  MECHANISM  OF  NATURE  299 

as  we  could  not  ignore  it  in  our  actions  if  we  would  without 
suffering  the  consequences ;  although  belief  in  universal  causation 
does  not  seem  to  be  necessary,  for  we  find  men  who  think  they 
are  quite  able  to  believe  in  luck  or  chance,  as  in  the  fall  of  dice, 
and  others  who  hold  that  our  own  rational  actions  are  no  part 
of  the  order  of  nature. 

It  is  clear,  however,  that,  as  living  beings,  we  are  compelled, 
by  our  nature,  to  respond  to  the  law  of  causation  or  take  the 
consequences,  and  that  in  this  sense  the  law  is  necessary  to  man 
as  man  just  as  food  and  drink  are  necessary;  but  as  it  by  no 
means  follows  that  we  are  to  have  food  and  drink,  or  that  a  man 
may  not  starve  himself,  so  it  may  not  follow  that,  because  confidence 
in  causation  is  organic  and  natural,  the  external  relations  to  which 
we  respond  are  fixed  or  necessary. 

The  responses  to  causation  which  are  part  of  our  nature  as 
living  men  are  continually  verified  and  amplified  and  perfected  and 
corrected  by  new  experience  with  every  hour  of  our  existence, 
until  old  age  is  inclined  to  suspect  that  experience  has  nothing 
new  to  offer;  but  the  support  which  individual  experience  gives 
to  this  law  is  as  nothing  in  comparison  with  that  which  we  find 
in  the  annals  of  scientific  progress,  —  in  the  systematic  observa- 
tions and  controlled  experiments  which  make  up  that  organized 
and  orderly  summary  of  the  experience  of  generation  after  gener- 
ation which  is  now  the  common  stock  of  all  educated  men. 

"  A  single  book  tells  us  more  than  Methuselah  could  have 
learned,  had  he  spent  every  waking  hour  of  his  thousand  years 
in  learning.  When  apparent  disorders  are  found  to  be  only  the 
recurrent  pulses  of  a  slow-working  order,  and  the  wonder  of  the 
year  becomes  the  commonplace  of  a  century;  when  repeated  and 
minute  examination  never  reveals  a  break  in  the  chain  of  causes 
and  effects ;  and  the  whole  edifice  of  practical  life  is  built  on  our 
faith  in  its  continuity,  —  the  belief  that  the  chain  has  never  been 
broken  and  will  never  be  broken  becomes  one  of  the  strongest 
and  most  justifiable  of  human  convictions."  ^ 

To  admit  that  response  to  causation  is  part  of  our  human 
constitution  is  one  thing,  but  it  is  quite  another  matter  to  assert 
that   we    know   why    one    event    must,    or   even   that   it   must,    be 

1  Huxley,    "Hume,"   p.   153. 


300  THE  FOUNDATIONS  OF  ZOOLOGY 

associated  with  another.  This  second  element  in  the  "  law  of 
causation"  would  never  have  obtained  a  moment's  credence  if  it 
were  not  brought  before  our  minds  in  intimate  relation  with  the 
great  natural  truth  of  the  other  element. 

"There  are,"  says  Herschel,  "truths  so  large,  so  general,  so 
all  pervading,  that  they  make  a  part  of  all  our  experience,  mix 
with  our  whole  intellectual  being,  and  imbue  all  our  judgments, 
erroneous  as  well  as  correct ;  in  this  sense,  at  least,  that  we 
never  err  so  far  as  to  place  ourselves  in  conscious  opposition  to 
them. 

"  Distorted  and  perverted  as  such  truths  may  be  in  their 
enunciation,  by  their  mixture  with  extraneous  error,  we  find  them 
still  outstanding,  redeeming  by  their  presence  and  ever  conse- 
crating  that   error."  ^ 

Such  a  truth  I  take  the  law  of  causation  to  be. 

All  writers  on  the  principles  of  science  agree  that  man  has 
as  yet  discovered  nothing  except  a  little  of  the  order  of  nature, 
and  that  the  reason  why  events  occur  in  one  order  rather  than 
another,  or  even  why  they  occur  in  any  order,  is  a  mystery  to 
which  nature  gives  us  no  answer;  for  even  if  natural  selection 
should  show  that  we  should  have  been  different  if  the  selective 
standard  had  been  different,  and  that  this  order  is  no  more  than 
might  have  been  expected  from  our  history,  this  is  no  reason 
why  the   things  we   expect   should  be  the  things  that  come  about. 

We  can  say  no  more  about  the  relation  between  events  and 
our  expectations  than  that  these  things  appear  together,  but  that 
nature  does  not  tell  us  why.  If  this  is  true,  is  it  not  clear  that 
we  are  in  no  position  to  say  of  any  event  that  it  cantiot  come 
about  in  the  absence  of  any  other  event,  although  we  may 
have   the  utmost  practical  confidence  that  it  will  not  come  about.'* 

We  cannot  well  do  without  the  word  cause,  and  Mill  has 
called  attention  to  the  obvious  fact  that  the  scientific  method  of 
investigating  cause  is  independent  of  metaphysical  analysis  of  what 
cause  means ;  although  exact  reasoning  about  nature  is  impossible 
unless  this  distinction  is  sharply  drawn.  A  recent  writer  on 
logic  tells  us :  "A  very  simple  analysis  of  ' cause '  is  sufficient 
for  the  purposes  of    scientific   inquiry.     What   we    call    a   cause  is 

1  Sir  J.  Herschel,  "  Essays,"  p.  270. 


THE  MECHANISM  OF  NATURE  301 

not  merely  antecedent  or  prior  in  time  to  what  we  call  its  effect- 
it  is  so  related  to  the  effect  that  if  it  or  its  equivalent  event  had 
not  happened,  the  effect  would  not  have  happened.  Anything  in 
the  absence  of  which  a  phenomenon  zvould  not  have  come  to  pass 
is  a  cause  in  the  ordinary  sense." 

No  one  can  object  to  this  analysis  of  the  ordinary  sense  of 
the  word  cause,  if  not  only  this  word  but  all  the  words  I  have 
put  in  italics  are  used  in  the  ordinary  sense;  but  when  using 
words  in  this  sense,  we  say  one  event  would  not  have  happened 
in  the  absence  of  another,  we  mean  only  that  belief  that  it  might 
so  happen  seems  inconsistent  with  what  we  chance  to  know  of 
the  past,  and  with  those  responses  which  we  make  in  virtue  of 
our  nature.  There  may  be  no  practical  difference  between  cer- 
tainty and  this  expectation,  if  it  is  shared  by  all  persons  in  whom 
we  have  confidence,  if  every  experiment  which  has  tested  it  has 
verified  it,  if  it  is  associated  in  our  minds  with  other  events  re- 
garding which  we  have  the  same  confidence,  and  if  our  organic 
responses  are  so  firmly  adjusted  to  this  association  that  we  fail 
to  discover  any  way  to  change  them  without  disaster.  Thus  put, 
the  analysis  of  the  word  cause  is  seen  to  have  no  bearing,  either 
positively  or  negatively,  upon  the  existence  of  a  necessary  law 
of  causation;  but  it  seems  to  me  to  be  all  science  warrants,  for 
our  ability  to  believe  in  the  order  of  nature  changes  daily  with 
our  knowledge  and  experience,  and  our  organic  responses  change 
slowly  through  selection. 

Perception  of  the  truth  that  our  knowledge  of  the  world  around 
us  is  knowledge  of  the  order  of  events,  and  that  we  know  no  reason 
why  events  should  be  orderly  except  that  the  fact  is  so,  is,  in  effect, 
an  admission  that  all  our  knowledge  of  nature  is  sensible  know- 
ledge. Whether  they  agree  with  Berkeley  that  objects  of  sense, 
or,  as  he  prefers  to  call  them,  ideas,  are  all  that  exist,  most  thought- 
ful men  of  science  agree  that  they  are  all  we  know  the  exist- 
ence of. 

"  Ideas  which  are  observed  to  be  connected  together  are,"  as 
Berkeley  points  out,  "  vulgarly  considered  under  the  relation  of 
cause  and  effect,  whereas,  in  strict  and  philosophic  truth,  they  are 
only  related  as  the  sign  and  the  thing  signified"    (13). 


302  THE  FOUNDATIONS  OF  ZOOLOGY 

"It  seems  evident,"  says  he,  "that  an  idea  can  be  only  like 
another  idea,  and  that  in  our  ideas,  or  immediate  objects  of  sense, 
there  is  nothing  of  Power,  Causality,  or  Agency  included"  (12). 
"How,  then,  can  you  tell,"  he  asks,  "whether  such  unknown  cause 
acts  arbitrarily  or  necessarily  ?  I  see  the  effects  or  appearances, 
and  I  know  that  effects  must  have  a  cause,  but  I  neither  see  nor 
know  that  their  connection  with  that  cause  is  necessary.  What- 
ever this  may  be,  I  am  sure  I  see  no  such  necessary  connec- 
tion" (30).i 

To  return  to  our  automatic  clock.  We  do  know,  as  a  matter 
of  fact,  that,  once  put  in  place  and  started,  it  may  be  expected  to 
keep  on  going,  without  farther  attention,  until  in  course  of  nature 
something  occurs  to  stop  it.  Some  tell  us,  therefore,  that  while 
the  mechanism  of  nature  may  need  a  starter,  it  is  self-sustaining 
after  it  is  once  started.  What  meaning  these  reasoners  attach  to 
the  word  self-sustainmg,  I  am  unable  to  conjecture,  unless  they 
mean  independent  of  human  users ;  but  their  logic  seems  to  have 
imposed  upon  no  less  shrewd  a  thinker  than  Bacon,  who  tells  us 
that  "  notwithstanding  God  hath  rested  and  ceased  from  creating 
since  the  first  Sabbath,  yet,  nevertheless,  he  doth  accomplish  and 
fulfil  his  divine  will  in  all  things,  great  and  small,  as  fully  and 
exactly  by  Providence,  as  he  would  by  miracle  and  new  creation, 
though  his  working  be  not  immediate  and  direct,  but  by  compass, 
not  violating  nature,  which  is  his  own  law  upon  the  creature." 

While  Bacon  took  all  knowledge  for  his  patrimony,  he  failed 
to  enjoy  his  birthright,  for  he  was  quite  unable  to  profit  by  his 
acquaintance  with  true  scientific  men  like  Harvey,  and  when  he 
speaks  of  violating  or  not  violating  nature,  he  exhibits  superficial 
and  erroneous  notions  of  science,  for  nothing  that  is  can  be  a  vio- 
lation of  nature,  since  nature  is  neither  more  nor  less  than  that 
which  is.  If  that  is  miraculous  which  is  not  accounted  for  by 
natural  law,  all  nature  is  miraculous ;  for  natural  laws  tell  us  only 
what  is,  not  why  it  is. 

Some  modern  students  unquestionably  think  as  Bacon  does. 
They  have  been  told  so  often  that  the  spread  of  mechanical  con- 
ceptions of  nature  must  necessarily  end  by  pushing  the  Creator  out 

^  Berkeley,  "Theory  of  Vision  Vindicated  and  Explained." 


THE  MECHANISM  OF  NATURE  303 

of  creation  that  they  have  come  to  believe  this ;  although  every 
great  teacher  of  the  principles  of  science  tells  them  their  infe- 
rence is  worthless.  We  fail,  on  analysis,  to  discover  any  a  priori 
foundation  for  the  law  of  conservation  of  energy,  the  law  of  the 
indestructibility  of  matter,  the  law  of  the  continuity  of  motion,  the 
law  of  natural'  causation,  or  any  necessary  or  universal  law  of 
nature.  If  we  pass  by,  for  the  present,  what  animal  automatism 
or  human  automatism  would  mean  if  it  were  established,  all  the 
meaning  we  are  able  to  find  in  the  automatic  clock,  or  in  the 
automatism  of  nature,  for  the  meaning  of  the  word  automaton,  as 
distinguished  from  instruments  and  structures,  is  an  orderly  mecha- 
nism which  is  worthy  of  confidence  and  independent  of  human 
users,  and  useful  to  them  who  know  how  to  use  it. 

Unless  sane  men  doubt  whether  the  mechanism  of  nature  is 
orderly  and  worthy  of  confidence  and  independent  for  the  most 
part  of  human  users,  and  useful  to  them  who  know  how  to  use 
it,  no  philosopher  has  as  yet  found  in  physical  science  any  basis 
for  a  philosophy  of  nature  which  is  not  the  common  property  of 
all  rational  beings.  I  fail  to  see  why  any  should  dread  the  exten- 
sion of  mechanical  conceptions  of  nature.  If  life  is  response  to 
the  order  of  nature,  he  who  dreads  or  fears  natural  knowledge 
seems  unworthy  of  the  conscious  life  of  manhood,  and  better  fitted 
for  that  of  a  turnip  or  a  clam.  These  things  have  the  benefit  of 
response  to  mechanical  principles  without  seeming  to  know  anything 
about  it ;  and  he  whom  these  principles  oppress  like  a  nightmare  might 
be  more  at  ease  if  he  were  a  turnip.  He  might  then  have  all 
the  benefit  of  mechanical  principles  without  the  horror  of  physical 
science  which  seems  as  subjective  as  the  horrors  of  delirium  tremens. 
The  sufferer  should  have  our  pity,  but  I  cannot  put  myself  in 
his  place,  for  nothing  seems  clearer  than  that  the  natural  common 
sense  of  man  would  preserve  him  from  all  horror  of  mechanics 
if  he  were  left  alone;  that  it  would,  on  the  contrary,  assure  him 
that  each  new  discovery  in  this  field  is  added  proof  of  his  sanity 
and  of  the  value  of  his  common  sense. 

If  any  believe  they  have  evidence  of  a  power  outside  nature, 
to  which  both  its  origin  and  its  maintenance  from  day  to  day  are 
due,  physical  science  tells  them  nothing  inconsistent  with  this  be- 
lief.    If  failure  to  find  any  sustaining  virtue  in  matter  and  motion 


304  THE  FOUNDATION'S   OF  ZOOLOGY 

is  evidence  of  an  external  sustaining  power,  physical  science  affords 
this  evidence;  but  no  one  who  admits  this  can  hope  to  escape 
calumny ;  although  it  seems  clear  that  the  man  of  science  is  right, 
and  that  theologians  must  some  time  admit  he  is  right,  and  thank 
him  for  standing  by  the  truth  in  evil  report  and  in  good  report ; 
for  refusing  to  admit  that  he  knows  the  laws  of  physical  nature 
in  any  way  except  as  observed  order. 

Stoutly  and  steadfastly  has  he  refused  to  assert  that  he  knows 
any  event  must  happen  because  some  other  event  has  happened. 
He  maintains  that  he  knows  nothing  of  causes  as  necessary  ante- 
cedents ;  nothing  of  effects  as  necessary  consequents.  He  has 
never  ceased  from  declaring  his  repudiation  of  Pindar's  concep- 
tion of  natural  law  as  the  Ruler  of  the  Mortals  and  the  Immortals ; 
or  as  the  ruler  of  anything  else,  even  the  fall  of  a  stone  or  a 
sparrow  to  the  ground. 

With  all  the  emphasis  he  can  command  does  he  aflfirm  that 
they  who  charge  him  with  belief  that  nature  is  governed  by  fixed 
or  necessary  mechanical  principles  are  totally  ignorant  of  the 
methods  and  accomplishments  of  science. 

If  any  still  fail  to  understand  him,  the  failure  must  be  due  to 
the  limitations  of  language,  or  to  ignorance,  or  to  natural  incapacity ; 
for  he  must  bear  in  mind,  with  Aristotle,  that  reasoning  does  not 
appeal  to  all,  but  only  to  those  whose  minds  are  prepared,  as 
ground  is  prepared  for  seed. 

The  belief  that  the  establishment  of  scientific  conceptions  of 
nature  shows  that,  after  the  first  creative  act,  the  Creator  has 
remained  subject,  like  a  human  legislator,  to  his  own  laws,  is  based 
upon  utter  misapprehension  of  science,  and  upon  absurd  and  irra- 
tional notions  of  natural  law. 

All  the  student  of  physical  science  is  able  to  discover  in  any 
automaton,  artificial  or  natural,  as  distinguished  from  instruments 
and  structures,  is  that  its  movements  are  orderly,  and  that  confi- 
dence in  them  is  reasonable  and  judicious.  This  seems  to  be  what 
the  word  automaton  means,  and  all  it  means;  ujiless  it  means  that 
our  confidence  in  the  usefulness  of  automata,  like  our  confidence 
in  the  usefulness  of  structures  and  instruments,  is  reasonable  and 
judicious. 

This  thesis  is  the  subject  of  the  next  section. 


THE  MECHANISM  OF  NATURE 


305 


No  one  who  does  not  answer  in  the  negative  the  absurd  ques- 
tion whether  life  is  worth  Hving  —  a  question  which  is  answered 
affirmatively  by  every  act  of  scientific  inquiry— can  ask  with  any 
serious  doubt  of  the  answer,  whether  the  attributes  of  living  things 
are  useful. 

"  The  opinion  which  disdaineth  our  life  is  ridiculous :  For  in  fine 
it  is  our  being.  It  is  our  all  in  all.  It  is  against  nature,  we  should 
disprise,  and  carelessly  set  ourselves  at  naught:  It  is  a  particular 
infirmitie,  and  which  is  not  seene  in  any  other  creature,  to  hate 
and  disdaine  himself."  ^ 

In  Romanes's  words,  "wherever  we  tap  organic  nature  it  seems 
to  flow  with  purpose."  The  whole  history  of  zoology  is  a  history 
of  the  discovery  of  the  adjustment  of  the  acts  of  living  things  to 
the  order  of  nature. 

The  discovery  of  the  chain  of  physical  causation  which  joins 
this  order  of  nature  to  these  adjustments,  by  means  of  natural 
selection,  tells  us  nothing  except  that  these  adjustments  are  no 
more  than  might  have  been  expected;  and  I  cannot  put  myself 
in  the  place  of  those  who  think  this  discovery  shows  that  the  fit- 
ness of  living  beings  is  not  real  fitness. 

He  who  admits  that  cats  are  part  of  nature,  and  that  skill  in 
catching  mice  is  important  to  the  race  of  cats,  must  admit  that 
nature  is,  so  far,  useful  to  itself  ;  nor,  while  the  standpoint  of  the 
mouse  must  not  be  forgotten,  do  I  see  how  proof  that  cats  are 
part  of  the  order  of  physical  nature  would  alter  the  case,  for  this 
would  only  prove  that  physical  nature  is,  so  far,  useful  to  itself. 
Proof  that  cats  are  automatic  and  mechanical,  from  beginning  to 
end,  would  show  that  their  whole  history  has  been  orderly  and 
what  might  have  been  expected,  but  it  would  not  disprove  any- 
thing we  now  know  about  them,  nor  tell  us  whether  their  actions 
are  necessary  or  unnecessary,  for  the  discovery  that  a  natural 
event  may  be  counted  on  with  confidence  tells  us  nothing  about 
its  origin  and  nothing  about  its  existence  except  what  we  know 
already. 

When  we  say  nature  is  orderly,  we  mean  each  event  may  be 
a  sign  which  leads  us  to  expect  other  events  with  confidence. 
When  we  say  the  attributes  of  living  things  are  useful  to  them,  we 

^  Montaigne,  "  A  Custom  of  the  He  of  Cea." 


306  THE  FOUNDATIONS  OF  ZOOLOGY 

mean  that  they  are  so  constituted  that  the  stimulus  of  one  event 
initiates  changes  which  are  so  adjusted  to  other  events  as  to  lead 
to  survival  in  the  struggle  for  existence.  As  this  adjustment  may- 
be perfected  and  improved  without  discoverable  limit,  and  as  all 
natural  knowledge  may  be  put  to  use,  has  not  our  belief  that  nature 
is  useful  the  same  basis  as  our  confidence  in  the  stability  of  nature? 

If  man  were  a  pure  intellect,  our  conviction  that  nature  is  orderly 
might  mean  no  more  than  that  events  are  signs  with  a  significance ; 
but  since  man  is  not  only  a  rational  being  but  a  living  thing,  each 
event  is  not  only  a  sign  which  tells  us  what  to  expect,  but  a 
warning  to  tell  us  what,  on  peril  of  consequences,  we  should 
prepare  for. 

Our  warrant  for  confidence  in  the  stability  of  nature  seems  to 
me  to  be  the  continuity  of  life ;  and  if  we  admit  that  life  is  worth 
living,  we  must  also  admit  that  the  evidence  that  the  order  of 
nature  is  useful  is  identical  with  the  evidence  that  there  is  order 
in  nature. 

If  the  artificial  production  of  living  beings  out  of  inorganic 
matter  should  ever  prove  that  their  fitness  is  "deducible"  from 
the  physical  properties  of  living  matter,  this  would  not  mean  that 
their  fitness  is  imaginary,  but  only  that  the  properties  of  certain 
forms  of  matter  are  useful  to  these  forms  of  matter. 

Some  tell  us,  however,  that  the  passage  from  the  properties  of 
matter  to  the  phenomena  of  life  is  unthinkable ;  but  they  who 
infer  that  this  passage  is  therefore  impossible,  must  remember  that 
the  passage  from  the  properties  of  the  stone  I  hold  in  my  hand 
to  the  fall  of  the  stone  would  be  equally  unthinkable  if  I  had  no 
experience  of  gravitation,  for  I  find  in  nature  no  reason  why  it 
should  fall  except  my  confidence  that  it  will ;  and  the  only  test  of 
the  objective  value  of  this  confidence  is  that  which  experience 
gives. 

No  great  brilliancy  or  nimbleness  of  wit  is  called  for  to  see  that 
the  discovery  that  things  do  take  place  in  order  is  no  reason  why 
they  should,  or  even  why  they  should  take  place  at  all.  They 
who  hold  that,  while  mind  is  free,  matter  is  bond,  seem  to  mean 
no  more  than  that  they  know  no  reason  why  their  mental  events 
must  take  place  in  order ;   but  unless  they  can  show  some  reason 


1 


THE  MECHANISM  OF  NATURE  307 

why  material  events  must  take  place  in  order,  I  do  not  see  what 
reason  they  have  for  thinking  matter  is  any  more  bond  than  mind. 

Many  authors  have  quoted  with  approval  Tyndall's  eloquent 
statement  of  his  conviction  that  the  passage  from  motion  to  mind 
is  unthinkable,  for  his  reasoning  seems  to  be  impregnable. 

"The  passage  from  the  physics  of  the  brain  to  the  correspond- 
ing facts  of  consciousness  is  unthinkable.  Granted  that  a  definite 
thought  and  a  definite  molecular  action  in  the  brain  occur  simul- 
taneously, we  do  not  possess  the  intellectual  organ,  nor  apparently 
any  rudiment  of  the  organ,  which  would  enable  us  to  pass,  by  a 
process  of  reasoning,  from  one  phenomenon  to  the  other.  They 
appear  together,  but  we  do  not  know  why.  Were  our  minds  and 
senses  so  expanded,  strengthened,  and  illuminated,  as  to  enable  us 
to  see  and  feel  the  very  molecules  of  the  brain  ;  were  we  capable 
of  following  all  their  motions,  all  their  groupings,  all  their  electri- 
cal discharges,  if  such  there  be ;  and  were  we  intimately  acquainted 
with  the  corresponding  states  of  thought  and  feeling,  we  should  be 
as  far  as  ever  from  the  solution  of  the  problem  :  How  are  these 
physical  processes  connected  with  the  facts  of  consciousness .-'  The 
chasm  between  the  two  classes  of  phenomena  would  still  remain 
intellectually  impassable." 

While  this  statement  of  the  case  seems  to  me  to  be  impreg- 
nable, it  does  not  seem  to  have  any  relevancy  or  any  particular 
significance,  unless  Professor  Tyndall  or  others  can  show  that  we 
have  some  organ  or  some  rudiment  of  an  organ  which  gives  us 
some  other  reason  why  an  unsupported  stone  should  fall  than 
the  fact  that  it  does  fall.  I  do  not  see  what  new  light  the  e.xpan- 
sion  and  strengthening  and  illumination  of  our  minds  and  senses 
could  be  expected  to  throw  on  the  matter ;  for  the  illumination  of 
the  molecules  of  the  brain  or  those  of  any  other  body,  until  they 
appeared  like  cannon-balls  rolling  in  a  ten-acre  lot,  would  not  tell 
why  a  collision  between  two  of  them  should  change  the  rate  or 
direction  of  their  motion.  We  could  only  say,  as  we  say  now,  that 
our  implicit  confidence  that  they  will  conform  to  Newton's  laws 
is  reasonable  and  judicious  because  in  all  human  experience  it  has 
never  been  disappointed.  If  Professor  Tyndall  should  assert  that 
this  implicit  confidence  is  itself  a  passage  from  one  physical  phe- 
nomenon to  another,  and  that  this  passage  is  so   far   thinkable,  a 


308  THE  FOUNDATIONS  OF  ZOOLOGY 

little  reflection  will  show  that  the  passage  from  physical  phenomena 
to  psychical  events  is  thinkable  in  exactly  the  same  way,  since  all 
plain  practical  folks  think  it  every  day  and  every  moment  of  their 
lives.  As  we  use  words,  a  mountain  is  physical,  and  to  see  a  moun- 
tain is  a  state  of  mind.  Is  not  our  confidence  that  if  Professor 
Tyndall  were  where  the  Alps  could  be  seen,  he  might  see  them  if 
he  had  his  eyesight,  as  reasonable  and  as  implicit  as  our  confi- 
dence that  a  collision  between  two  molecules  will  change  their 
motion  t  If  we  can  be  said  to  pass  by  a  process  of  reasoning 
from  the  motion  of  two  molecules  before  impact  to  their  motion 
afterwards,  we  can  be  said  to  pass,  in  the  same  way,  from  a  physi- 
cal burn  to  a  psychical  pain ;  for  we  have  no  reason  to  doubt 
and  every  reason  to  expect  that  a  burn  will  hurt.  Tyndall's  asser- 
tion that  the  passage  from  the  physics  of  the  brain  to  the  facts 
of  consciousness  is  unthinkable,  that  they  appear  together,  but  that 
nature  does  not  tell  us  why,  might  be  a  contribution  to  human 
wisdom  if  we  were  able  to  discover  in  nature  any  reason  why 
physical  phenomena  themselves  appear  together  except  the  fact 
that  they  do. 

"  Modern  science,"  says  Huxley,  with  an  insight  more  profound 
than  Tyndall's,  "admits  that  there  are  two  worlds  to  be  considered, 
the  one  physical  and  the  other  psychical,  and  that  though  there  is 
a  most  intimate  relation  and  intercommunication  between  the  tivo, 
the  bridge  from  one  to  the  other  has  yet  to  be  found ;  that  their 
phenomena  run,  not  in  one  series,  but  along  parallel  lines."  ^ 

The  reduction  of  the  phenomena  of  life  to  those  mechanical 
principles  which  hold  good  in  the  inorganic  world  would  unques- 
tionably show  that  these  two  worlds  are  in  fact  different  aspects 
of  one  and  the  same  world.  If  such  a  discovery  should  ever  be 
made,  we  might  well  hope  for  untold  practical  benefits  to  man- 
kind, like  those  which  have  followed  every  great  advance  in  know- 
ledge, but  I  cannot  see  how  it  could  possibly  show  that  man  is 
anything  else  than  man,  or  mind  anything  but  mind ;  for  when 
we  say  we  are  able  to  pass  from  one  physical  event  to  another 
physical  event,  all  we  mean  is  that  one  of  these  events  is  the  sign 
which    leads    us   to    look  for  the  other  with  confidence.     We  most 

1 "  Pseudo-Scientific  Realism,"  p.  62. 


THE  MECHANISM   OF  NATURE 


309 


assuredly  know  no  reason  why  they  should  stand  in  this  relation, 
and  we  can  only  say  of  them  that  they  occur  together,  but  that 
nature  does  not  tell  us  why. 

They  who  assert  that  the  production  of  living  beings  out  of 
inorganic  matter  would  show  that  matter  is  the  efficient  cause  of 
mind,  totally  mistake  the  nature  of  scientific  evidence ;  for  we  may 
say  of  physical  events  that  while  they  run  on  lines  that  are  so  far 
parallel  that  one  may  be  the  sign  which  leads  us  to  expect  others, 
the  bridge  which  joins  them  has  never  been  found  in  nature. 

As  matters  are  at  present  we  have  the  same  sort  of  reason 
for  confidence  that  certain  psychical  events  will  follow  certain 
physical  events  and  that  certain  physical  events  will  follow  cer- 
tain psychical  ones ;  that  the  sensation  of  vision  will  follow  the 
opening  of  our  eyes,  and  that  a  quickened  pulse  will  follow 
anger;  that  we  have  for  confidence  in  the  physical  order  of 
nature. 

Even  the  fantastical  desire  to  show  we  can  do  as  we  like  by 
some  capricious  action,  is  no  more  than  a  shrewd  witness  might 
have  expected ;  and  psychical  events  are  as  orderly  as  physical 
events.  Surely  no  one  supposes  that  while  physical  matters  are 
orderly,  psychical  matters  are  given  over  to  chance. 

"  For  what  is  meant  by  liberty,  when  applied  to  voluntary 
actions .-'  We  cannot  surely  mean  that  actions  have  so  little  con- 
nection with  motives,  inclinations,  and  circumstances  that  one 
doth  not  follow  with  a  certain  degree  of  uniformity  from  the 
other,  and  that  one  affords  no  inference  by  which  we  can  con- 
clude the  existence  of  the  other.  For  these  are  plain  and 
acknowledged  matters  of  fact."  ^ 

If  any  one  assert  that  while  he  acts  from  motives,  like  a 
rational  being,  and  in  the  way  he  might  reasonably  be  expected 
to  act,  he  is  nevertheless  free  to  do  as  he  likes,  because  there 
is  no  necessary  connection  between  his  actions  and  his  motives, 
he  must  remember  that,  while  no  one  disputes  his  freedom,  we 
know  no  necessary  connection  between  physical  phenomena,  and 
that,  if  the  stone  I  drop  from  my  hand  were  to  assert  that  it  is 
free  to  do  as  it  likes,  I  should  have  to  admit  that,  for  all  I  know 
to  the  contrary,  this  assertion  may  be  true ;  for  all  I  know  of  the 

1  Hume,   as  quoted  by   Huxley. 


3IO  THE  FOUNDATIONS  OF  ZOOLOGY 

matter  is  that  all  stones  thus  placed  have  done  as  I  expected, 
and  that  I  have  not  the  slightest  reason  to  suppose  that  any- 
stone  will  act  differently,  or  to  believe  that  it  either  is  or  is  not 
free  to  do  as  it  likes. 

The  reason  why  the  animistic  belief  that  everything  is  alive,  which 
once  prevailed  among  all  men,  has  passed  out  of  the  modern  mind 
is  not  that  it  has  been  proved  untrue,  but  that  we  find  no  evidence 
of  its  truth,  and  no  value  in  its  practical  application. 

I  do  find  evidence  that  I  am  free,  and  while  my  reason  has  little 
value  in  open  market,  its  value  to  me  is  great. 

Every  one  who  is  called  upon  to  develop  and  perfect  the 
nature  of  a  child  takes  its  ability  to  do  as  it  likes  for  granted, 
and  tries  to  find  out  why  it  likes  to  do  what  it  does,  and  to  sub- 
stitute wise  and  prudent  motives  for  superficial  or  pernicious 
ones ;  and  the  method  by  which  a  crafty  schemer  manipulates 
his  fellow-men  for  his  own  ends  is  essentially  the  same. 

We  know  we  are  free  to  do  as  we  like  ;  and  we  also  know 
there  are  reasons  why  we  like  to  do  as  we  do. 

The  reduction  of  all  the  phenomena  of  life  to  mechanical 
principles  would  show  that  our  likings  and  dislikings  are  what 
they  might  have  been  expected  to  be. 

It  is  hard  to  see  why  one  who  admits  that  the  nature  which 
tells  us  some  actions  are  pleasant  and  others  painful,  some  wise 
and  others  foolish,  some  right  and  others  wrong,  is  natural, 
should  dread  the  prevalence  of  mechanical  explanations  of 
human  nature ;  for  it  seems  clear  that  they  would  not  alter  or  do 
away  with  any  one  thing  that  we  know  now.  No  one  who  be- 
lieves duty  and  moral  responsibility  are  natural  would  find  any 
reason  for  changing  his  belief  on  proof  that  our  nature  is  what 
it  might  have  been  expected  to  be. 

The  opinion  that  there  is  any  incompatibility  between  natural 
law  and  liberty  has  arisen  out  of  the  belief  that  so  far  as  nature 
is  reducible  to  laws  it  is  necessary ;  and  the  clear  recognition  of 
the  truth  that  a  natural  law  is  simply  a  generalized  statement  of 
our  confidence  that  nature  is  orderly,  should  show  that  this 
opinion  is  idle ;  for  while  the  antithesis  to  necessary  may  be 
arbitrary^  the  antithesis  to  order  is  disorder. 


THE  MECHANISM  OF  NATURE  311 

In  the  famous  argument  by  which  Butler  shows  that  the 
assertion  that  nature  is  necessary  is  no  answer  to  the  question 
whether  it  is  intended,  he  supposes  that  a  fatalist  and  one  who 
believes  himself  a  free   agent  are  disputing  together. 

The  reasoning,  while  conclusive,  is  hard  to  follow ;  but  if  we 
substitute  for  fatalist,  or  one  who  believes  whatever  is  is  neces- 
sary, the  word  naturalist,  or  one  who  believes  whatever  is  is 
orderly,  and  for  the  word  necessary  the  word  orderly,  the  argu- 
ment becomes  so  simple  that  it  seems  like  a  parody. 

"  Suppose,"  he  would  say  if  this  change  were  made,  "  that  one 
who  was  a  naturalist  and  one  who  kept  to  his  natural  sense  of 
things,  and  believed  himself  a  free  agent,  were  disputing  together, 
and  vindicating  their  respective  opinions,  and  they  should  happen 
to  instance  a  house ;  they  would  agree  that  it  was  built  by  an  archi- 
tect. Their  difference  concerning  order  and  freedom  would  occa- 
sion no  difference  of  judgment  concerning  this  ;  but  only  concerning 
another  matter, — whether  the  architect  built  it  as  might  have  been 
expected  or  not  \_necessarily  or  freely,  in  the  original.] 

"When  it  is  said  by  a  naturalist  that  the  whole  constitution  of 
nature,  the  actions  of  men,  everything,  and  every  mode  and  circum- 
stance of  everything  is  orderly,  and  could  not  reasonably  have  been 
expected  to  have  been  otherwise,  it  is  to  be  observed  that  this 
order  doth  not  exclude  deliberation,  choice,  preference,  and  acting 
from  certain  principles,  and  to  certain  ends ;  because  all  this  is  a 
matter  of  undoubted  experience  acknowledged  by  all,  and  what 
every  man  may  every  moment  be  conscious  of.  Hence  it  follows 
that  order,  alone  and  of  itself,  is  in  no  sort  an  account  of  the  con- 
stitution of  nature,  and  how  things  came  to  be  and  to  continue  as 
they  are  ;  but  only  an  account  of  this  circumstance  relating  to  their 
origin  and  continuance,  that  they  could  not  reasonably  have  been 
expected  to  have  been  otherwise  than  they  are  and  have  been.  The 
assertion  that  everything  is  in  order  of  natiire  is  not  an  answer  to 
the  question  whether  the  world  came  into  being  as  it  is  by  an 
intelligent  Agent  forming  it  thus,  or  not;  but  to  quite  another 
question, — whether  it  came  into  being  as  it  is  in  that  way  and 
manner  which  we  call  orderly,  or  in  that  way  and  manner  which  we 
call  ....-'"  In  the  original  the  last  word  is  freely,  as  contrasted 
with  necessarily ;  but  while  I  have  substituted  orderly  for  necessarily. 


3X2  THE  FOUNDATIONS  OF  ZOOLOGY 

ilie  substitution  of  disorderly  for  freely  would  make  the  reasoning 
so  simple  as  to  be  almost  ludicrous ;  yet  I  am  not  able  to  find  any 
antithesis  to  order  except-  disorder. 

Nor  can  I  discover  what  bearing  proof  that  our  actions  are  what 
might  have  been  expected  of  us  has  on  the  question  whether  we  are 
free  to  do  as  we  choose,  unless  we  choose  to  do  and  succeed  in  doing 
utterly  inconsequent  and  irrational  things. 

Since  the  discovery  that  the  phenomena  of  nature  do  take  place 
in  order  does  not  show  why  they  take  place  in  order,  or  even 
why  they  should  take  place  at  all,  is  it  not  plain  that  the  discovery 
of  the  order  of  nature  has  no  bearing  on  the  origin  or  on  the 
reality  of  anything  in  nature .-' 

Is  it  not  equally  clear  that  the  reduction  of  all  the  phenomena 
of  nature,  including  those  of  life  and  mind,  to  mechanical  princi- 
ples, would  not  disprove  the  reality  or  the  value  of  any  one  thing 
we  discover  in  our  nature .-' 

Many  will,  no  doubt,  receive  with  incredulity  the  assertion  that 
the  ultimate  establishment  of  mechanical  conceptions  of  life  has 
no  bearing,  either  positively  or  negatively,  upon  the  validity  of 
such  beliefs  as  the  doctrine  of  immortality,  for  example.  The 
opinion  that  life  may  be  deducible  from  the  properties  of  protoplasm 
has,  by  almost  universal  consent,  been  held  to  involve  the  admission 
that  the  destruction  of  the  living  organism  is,  of  necessity,  the  anni- 
hilation of  life.  Yet  it  seems  clear  that  this  deduction  is  utterly 
baseless  and  unscientific ;  for  if  the  views  I  have  set  forth  in  this 
lecture  —  views  held  by  many  thoughtful  men  of  science;  views  in 
no  way  original  with  me — are  accepted,  and  if  it  be  admitted  that 
we  find  in  nature  no  reason  why  events  should  occur  together  except 
the  fact  that  they  do,  is  it  not  clear  that  we  can  give  no  reason 
why  life  and  protoplasm  should  be  associated  except  the  fact  that 
they  are }  And  is  it  not  equally  clear  that  this  is  no  reason  why 
they  may  not  exist  separately .'' 

Berkeley  tells  us  it  is  to  all  intents  and  purposes  atheistical 
"to  make  man  a  necessary  agent";  but  they  who  agree  with 
him  that  while  ideas  which  are  observed  to  be  connected  are, 
vulgarly  considered  under  the  relation  of  cause  and  effect,  they  are, 
in   strict  and  philosophic  truth,   known  to  be   related  only  as  the 


THE  MECHANISM   OF  NATURE  313 

sign  and  the  thing  signified,  will  fail  to  see  how  proof  that  man 
is  mechanical  and  automatic  could  show  that  he  is  a  necessary 
agent;  for  science  knows  no  necessity  except  the  logical  necessity 
for  stopping  where  the  evidence  stops. 

I  fail  to  see  why  any  one  should  find,  in  the  extension  of  me- 
chanical conceptions  of  nature,  any  evidence  "  that  right  deductions 
from  true  principles  should  ever  end  in  consequences  which  cannot 
be  maintained  or  made  consistent." 

So  far  as  the  word  necessity  means  anything  to  us,  as  living 
beings,  it  is  synonymous  with  the  blindness  of  ignorance.  The 
crab  that  finds  and  uses  a  house  does  nothing  that  might  not 
have  been  expected ;  and  since  natural  responses  often  mislead  and 
prove  injurious  or  even  destructive,  actions  that  are  due  to  nature 
are  commonly  said  to  be  blind  or  necessary ;  but  our  own  con- 
scious experience  does  not  change  our  nature ;  for  it  only  "  unravels 
our  prejudices  and  mistakes,  untwisting  the  closest  connections,  dis- 
tinguishing things  that  are  different,  instead  of  confused  and  per- 
plexed, giving  us  distinct  views,  gradually  correcting  our  judgment, 
and  reducing  it  to  a  philosophical  exactness." 

Since  this  is  so,  does  not  each  new  discovery  in  the  province 
of  zoology  give  added  meaning  to  the  declaration  that  it  is  the 
truth  that  shall  make  us  free  ? 


LECTURE    XIII 

LOUIS   AGASSIZ   AND   GEORGE   BERKELEY 


"Those  highly  magnifie  Him,  whose  judicious  inquiry  into  His  Acts,  and  deliberate 
research  into  His  Creatures,  return  the  duty  of  a  devout  and  learned  admiration."  —  Browne, 
"  Religio  Medici." 


LECTURE    XIII 

LOUIS   AGASSIZ   AND   GEORGE   BERKELEY 

Whether  the  Origin  of  Species  has  or  has  not  any  bearing  on 
the  argument  from  design,  it  clearly  has  very  obvious  and  positive 
bearing  on  certain  arguments  that  have  been  thought  to  prove  de- 
sign ;  although  belief  that  nature  gives  evidence  of  intention  may  be 
held  by  those  who  doubt  whether  it  affords  any  proof  of  contriv- 
ance—  of  any  use  of  instruments  —  that  is  not  itself  a  part  of  the 
order  of  nature.  While  every  phase  of  the  teleological  argument 
which  our  faculties  permit  has,  no  doubt,  been  considered  by  shrewd 
thinkers  long  ago,  the  work  of  Wallace  and  Darwin  has  brought 
clearly  and  distinctly  before  all  the  question  whether  it  is  contrivance 

—  the  use  of  means  or  instruments,  and  the  overcoming  of  difficulties 

—  or  nature  itself,  which  the  teleologists  believe  to  prove  design.  So 
far  as  the  limitations  of  human  speech  are  adequate  to  put  it  into 
words,  the  peculiar  teleological  problem  of  the  nineteenth  century 
seems  to  be  whether  we  must  prove  contrivance,  or  interference  with 
nature,  in  order  to  show  intention ;  for  it  is  now  clear  to  us,  as  it 
never  has  been  before,  that,  even  if  it  be  not  impossible,  it  is  very 
difficult  to  show  the  occurrence  of  any  planning  or  contriving  that 
is  not  itself  a  part  of  the  orderly  course  of  nature,  admitting  of  a 
mechanical  explanation;  nor  does  it  seem  judicious  or  clear  sighted 
to  base  natural  theology  upon  anything  else  than  nature. 

These  two  elements,  the  argument  from  contrivance,  and  the 
argument  from  intention,  are  sometimes  distinguished  by  the  writers 
on  natural  theology,  although  none  of  them,  so  far  as  I  can  discover, 
keeps  the  distinction  clearly  and  constantly  in  mind.  In  fact,  most 
of  them  seem  to  me  to  so  entangle  these  two  points  of  view  as  to 
show  that  they  fail  to  attach  any  importance  to  the  distinction 
between  them ;  although   two  great  thinkers,  George  Berkeley  and 

317 


3l8  THE  FOUNDATIONS  OF  ZOOLOGY 

Louis  Agassiz,  base  their  reasoning  upon  nature  itself,  rather  than 
upon  evidence  of  contrivance  in  nature. 

Agassiz's  Essay  on  Classification,  the  last  of  the  notable  works 
on  natural  theology,  was  published  in  1857,  as  part  of  his  "Contribu- 
tions to  the  Natural  History  of  the  United  States." 

The  writer  was  a  man  of  transcendent  genius  for  scientific  dis- 
covery, with  intense  earnestness  and  enthusiasm  for  the  pursuit  of 
truth,  and  rare  eloquence  and  literary  skill.  If  any  man  was  devoted 
to  the  cause  of  truth  and  determined  to  accept  it  whatever  it  might 
prove  to  be,  that  man  was  Agassiz ;  for  while  his  impulses  were 
notably  devout  and  reverential,  he  proved,  on  many  occasions, 
that  he  was  fearless  and  independent  in  the  search  for  truth.  It 
is  no  disparagement  to  Buckland,  and  Bell,  and  Chalmers,  and  the 
other  authors  of  the  Bridgewater  Treatises  to  assert  that  Agassiz 
far  surpassed  them  all  in  acquaintance  with  the  methods  which 
lead  to  success  in  the  interpretation  of  nature,  and  in  ability  to 
treat  the  problems  of  natural  theology  from  the  standpoint  of  the 
zoologist. 

He  handles  the  subject  in  a  far  more  comprehensive  way  than 
any  of  these  writers,  for  he  does  not  hesitate  to  assert  that  their 
attempts  to  find  evidence  of  design  in  the  contrivances  of  living 
bodies  is  unscientific  and  wrong  in  principle. 

"  The  argument  for  the  existence  of  an  intelligent  Creator,"  he 
tells  us,  "  is  generally  drawn  from  the  adaptation  of  means  to  ends, 
upon  which  the  Bridgewater  Treatises,  for  example,  have  been 
based.  But  this  does  not  appear  to  me  to  cover  the  whole  ground, 
for  we  can  conceive  that  the  natural  action  of  objects  upon  each 
other  should  result  in  a  final  fitness  of  the  universe,  and  thus  pro- 
duce a  harmonious  whole ;  nor  does  the  argument  derived  from  the 
connection  of  organs  and  functions  seem  to  me  more  satisfactory, 
for  beyond  certain  limits  it  is  not  even  true." 

He  therefore  attempts  to  put  natural  theology  upon  a  much 
broader  basis ;  for  he  finds  reason  to  believe  that  the  facts  which 
are  studied  by  the  naturalist  —  the  phenomena  of  geological  succes- 
sion and  geographical  distribution,  of  embryology  and  anatomy,  of 
systematic  botany  and  zoology;  in  a  word,  all  the  data  of  the  natural 
sciences  —  are  a  language  in  which  the  Creator  tells  us  the  story 
of  creation  for  our   delight   and    instruction   and   advantage;    and 


LOUIS  AGASSIZ  AATD   GEORGE  BERKELEY  319 

that  when  we  use  such  phrases  as  the  "language  of  nature," 
and  the  "interpretation  of  nature,"  our  words  are  not  figurative,  but 
literal. 

It  is  not  because  we  fiind  contrivances  in  nature,  but  because 
the  order  of  nature  is  one  consistent  and  harmonious  whole,  that 
he  holds  it  to  be  intended. 

"  In  their  respective  great  types,  the  phenomena  of  animal  life 
correspond  to  one  another,  whether  we  compare  their  rank  as  de- 
termined by  structural  complication  with  the  phases  of  their  growth, 
or  with  their  succession  in  past  geological  ages ;  whether  we  com- 
pare this  succession  with  their  embryonic  growth,  or  all  these 
different  relations  with  each  other  and  with  the  geographical  dis- 
tribution of  animals  upon  earth.  The  same  series  everywhere ! 
The  connection,  however,  between  the  facts,  it  is  easily  seen,  is 
only  intellectual,  and  implies,  therefore,  the  agency  of  Intellect  as 
its  first  cause." 

He  holds  that  this  truth  is  most  clearly  shown  by  those  system- 
atic affinities  which  make  out  of  the  individual  animals  and  plants 
a  consistent  and  harmonious  whole,  a  realm  of  nature ;  and  he 
calls  his  work  an  Essay  on  Classification. 

"  The  division  of  animals  according  to  branch,  class,  order, 
family,  genius,  and  species,  by  which  we  express  the  results  of 
our  investigation  into  the  relations  of  the  animal  kingdom,  and 
which  constitute  the  first  question  respecting  the  systems  of  Natural 
History  which  we  have  to  consider,  seems  to  me  to  deserve  the 
consideration  of  all  thoughtful  minds.  Are  these  divisions  artificial 
or  natural .-'  Are  they  the  devices  of  the  human  mind  to  classify 
and  arrange  our  knowledge  in  such  a  manner  as  to  bring  it  more 
readily  within  our  grasp  and  facilitate  further  investigation,  or 
have  they  been  instituted  by  the  Divine  Intelligence  as  categories 
of  his  mode  of  thinking .?  Have  we  perhaps  thus  far  been  only 
the  unconscious  interpreters  of  a  Divine  conception,  in  our  attempts 
to  expound  nature?  and  when,  in  our  pride  of  philosophy,  we 
thought  we  were  inventing  systems  of  science,  and  classifying 
creation  by  the  force  of  our  own  reason,  have  we  followed  only, 
and  reproduced,  in  our  imperfect  expressions,  the  plan  whose 
foundations  in  the  dawn  of  creation,  and  the  development  of  which, 
we  are   laboriously  studying,  —  thinking   as  we   arrange   our    frag- 


320  THE  FOUiVDATIO/VS   OF  ZOOLOGY 

mentary  knowledge,  that  we  are  anew  introducing  order  into 
chaos  ?  Is  this  order  the  result  of  the  exertion  of  human  skill 
and  ingenuity,  or  is  it  inherent  in  the  objects  themselves,  so  that 
the  intelligent  student  of  Natural  History  is  led  unconsciously, 
by  the  study  of  the  animal  kingdom  itself,  to  those  conclusions, 
the  great  divisions  under  which  he  arranges  animals  being  indeed 
but  the  headings  to  the  chapters  of  the  great  book  which  he  is 
reading  ? " 

There  may  still  be,  here  and  there,  a  writer  on  "  logic "  who 
holds  that  since  zoology  is  a  "  classificatory  "  science,  the  work  of 
the  naturalist  is  like  that  of  one  who  arranges  and  tickets  books 
in  a  library  for  ease  of  reference ;  but  the  modern  student  of  science 
reads  such  assertions  with  a  sad  smile  that  one  should  be  so  igno- 
rant ;  for  he  is  as  fully  convinced  as  Agassiz  that  the  realm  of 
living  nature  is  a  consistent  and  harmonious  whole,  and  that  the 
work  of  the  naturalist  is  to  discover  and  not  to  create ;  for  he  bases 
all  his  work  upon  the  conviction  that  "  animals  are  linked  together 
as  closely  by  their  mode  of  development,  by  their  relative  standing 
in  their  respective  classes,  by  the  order  in  which  they  have  made 
their  appearance  upon  earth,  by  their  geographical  distribution, 
and  generally  by  their  connection  with  the  world  in  which  they 
live,  as  by  their  anatomy." 

Since  all  now  admit  the  validity  of  this  basis  for  the  argument 
of  Agassiz,  why  has  the  work  of  this  man  of  great  genius  been 
without  perceptible  influence  on  modern  thought ;  while  the  work 
of  much  less  able  men,  like  Paley,  was  for  many  years  an  im- 
portant educational  influence  ? 

Why  do  not  modern  naturalists  agree  with  Agassiz,  that  "  all 
organized  beings  exhibit  in  themselves  all  these  categories  of 
structure  and  of  existence  upon  which  a  natural  system  is  founded, 
in  such  a  manner  that,  in  tracing  it,  the  human  mind  is  only  trans- 
lating into  human  language  the  Divine  thoughts  expressed  in 
nature  in  living  realities  "  ? 

Agassiz  holds  that  "  in  one  word,  all  these  facts  in  their  natural 
connection  proclaim  aloud  the  One  God,  whom  man  may  know, 
adore,  and  love ;  and  Natural  History  must,  in  good  time,  become 
the  analysis  of  the  thoughts  of  the  Creator  of  the  Universe,  as 
manifested  in  the  animal  and  vegetable  kingdoms." 


LOUIS  AGASSIZ  AND   GEORGE  BERKELEY  32 1 

The  modern  naturalist  knows  that  while  the  best  powers  of 
the  best  minds  may  find  endless  pleasure  and  profitable  employ- 
ment in  the  study  of  those  relations  which  bind  the  living  world 
together  into  one  coherent  whole,  these  relations  include  far  more 
than  man  can  ever  hope  to  master ;  more  in  delicacy  and  perfec- 
tion than  his  microscope  can  ever  reveal ;  more  in  intricacy  and 
complexity  than  his  senses  can  follow;  more  in  extent  of  space 
and  time  than  the  utmost  range  of  his  powers ;  far  more  of  the 
network  of  physical  causation  than  his  intellect  can  grasp. 

If  he  also  knows  that  his  work  is  beneficial  to  himself  and  to 
all  mankind;  that  his  place  among  men  is  one  of  usefulness;  that 
the  study  of  living  things  and  their  ways  and  works  is  good  and 
pleasant  and  instructive, — why  does  he  hesitate  to  believe,  with 
Agassiz,  that  all  this  is  intended,  and  that  it  proves  that  nature 
is  a  language  ? 

"  If  the  power  of  thinking  connectedly  is  the  privilege  of 
cultivated  minds  only ;  if  the  power  of  combining  different  thoughts, 
and  of  drawing  from  them  new  thoughts,  is  a  still  rarer  privilege 
of  a  few  superior  minds;  if  the  ability  to  trace  simultaneously 
several  trains  of  thought  is  such  an  extraordinary  gift,  that  the 
few  cases  in  which  evidence  of  this  kind  has  been  presented  have 
become  a  matter  of  historical  record  (Caesar  dictating  several  let- 
ters at  the  same  time) ;  if  all  this  is  only  possible  to  the  highest 
intellectual  powers, —  shall  we  by  any  false  argumentation  allow  our- 
selves to  deny  the  intervention  of  a  supreme  intellect  in  calling 
into  existence  combinations  in  nature  by  the  side  of  which  all 
human   conceptions  are  child's  play  ?  " 

It  is  a  well-known  fact  that  modern  naturalists  have  refused 
to  admit  the  cogency  of  Agassiz's  reasoning,  and  all  must  feel 
an  interest  in  the  reason  why ;  for  it  may  be  that  this  is  due  to 
some  error  in  the  method  by  which  Agassiz  undertook  to  prove 
his  thesis,  rather  than  to  any  weakness  in  the  thesis  itself. 

In  order  to  prove  that  natural  history  is  a  language  which  we 
learn  and  listen  to,  to  our  entertainment  and  profit  and  instruction, 
he  holds  it  essential  to  prove  that  it  is  nothincr  but  a  language ; 
that  the  relations  between  living  things  and  the  world  about  them, 
being  ideal  relations,  cannot  possibly  be  physical  ones  also  ;  that 
our  "laws  of  biology"  are  not  "necessary"  but  "arbitrary." 


322  THE  FOUNDATIONS  OF  ZOOLOGY 

The  whole  aim  and  purpose  of  the  Essay  on  Classification  is 
to  prove  that  all  the  general  laws  of  natural  science  are  "cate- 
gories of  thought,"  by  an  attempt  to  show  that  they  are  nothing 
but  categories  of  thought,  and  that  no  physical  explanation  of 
them  is  possible. 

In  1859,  or  less  than  two  years  after  the  publication  of  the 
Essay  on  Classification,  the  appearance  of  the  "Origin  of  Species" 
brought  about  a  revolution  in  our  conceptions  of  natural  history, 
for  it  made  clear  the  mechanical  explanation  of  some  of  the 
general  laws  of  which  Agassiz  had  told  us  no  such  explanation 
is  possible.  It  is  because  the  work  of  Wallace  and  Darwin  has 
convinced  naturalists  that  species  have  arisen,  in  course  of  nature, 
through  influences  that  are  still  at  work,  that  many  modern  stu- 
dents have  refused  to  follow  Agassiz  in  the  assertion  that  the 
laws  of  their  science  are  "  arbitrary,"  for  they  hold  that  these 
laws  are  neither  arbitrary  nor  necessary,  l>ut  natural. 

As  Agassiz  used,  as  the  basis  of  his  thesis  that  nature  is  a 
language,  the  assertion  that  the  laws  of  living  nature  are  not 
mechanical,  many  of  the  working  naturalists  of  our  day,  know- 
ing, in  part  at  least,  the  physical  explanation  of  these  laws,  have 
refused  to  share  his  conviction  that  nature  is  a  language;  for  it 
is  the  fate  of  beliefs  which  are  upheld  by  fallacious  reasoning  to 
suffer  from  the  mistakes  of  their  supporters.  It  is  clear,  how- 
ever, that  error  on  the  part  of  the  advocate  of  an  opinion  is  no 
proof  of  error  in  the  opinion  itself.  The  intuitions  which  told 
Agassiz  that  nature  is  a  language,  which  we  learn  to  our  delight 
and  profit  and  instruction,  may  have  been  sound  and  trustworthy 
and  fruitful  in  results,  even  if  the  reasons  he  gives  for  this  con- 
viction are  at  fault. 

An  illustration  may  make  this  clear.  As  the  same  thought 
may  be  expressed  in  various  ways  in  different  languages,  and 
as  even  in  the  same  language  the  same  sounds  or  letters  may 
have  many  meanings,  it  is  clear  that  there  is  no  "  necessary " 
connection  between  words  and  the  things  they  signify ;  for  we 
might  call  black  white,  and  white  black,  without  confusion,  if  all 
who  use  our  language  were  agreed  upon  the  meaning  of  these 
words.  As  the  relation  between  words  and  the  things  they  signify 
is  not  "  necessary,"  it  has  seemed  to  some   that  it  is  "  arbitrary  " ; 


LOUIS  AGASSIZ  AND   GEORGE  BERKELEY  323 

but  one  of  the  results  of  the  publication  of  the  "  Origin  of  Species  " 
has  been  to  awaken  new  interest  in  the  science  of  philology,  and 
to  promote  the  progress  of  this  science.  We  now  know  that, 
far  from  being  arbitrary,  words  and  phrases  and  grammatical 
forms  contain  in  themselves  a  record  of  their  history;  a  record 
which  often  shows  how  they  have  come  to  be  used  as  they  are. 
Nothing  compels  me  to  use  one  word  rather  than  another,  or 
even  to  write  at  all ;  yet  it  has  been  found,  by  statistical  methods, 
that  choice  of  words  by  an  author  is  as  mechanical  and  orderly 
as  the  chest  measurements  on  page  157;  for  it  is  found  that  if 
the  proportion  in  which  common  words  are  used  be  computed 
from  a  hundred  pages  of  an  author,  this  same  proportion  will  be 
closely  adhered  to  in  all  his  works.  His  use  of  words  is  not 
necessary,  for  he  is  free  to  write  and  to  speak  as  he  chooses,  and 
may  justly,  as  well  as  legally,  be  held  responsible  for  his  words ; 
but  his  choice  conforms  to  a  statistical  type,  and  is  as  mechanical 
as  the  sizes  and  velocities  of  the  planets  in  their  orbits.  I  make 
my  sentences  long  and  complicated,  or  short  and  simple,  as  I 
think  best  for  the  reader,  for  no  particular  length  is  necessary ; 
yet  a  tabulation  will  show  that,  while  some  are  short  and  some 
long,  there  is,  for  each  writer,  a  mean  or  average  sentence-length, 
and  that  sentences  which  exceed  this  length  in  any  specified 
degree  are  exactly  equal  in  frequency  to  those  which  fall  short 
of  the  average  in  the  same  degree. 

Does  any  one  think  for  an  instant  that  language  is  any  the 
less  valuable  now  than  it  was  before  this  discovery  was  made } 
No  one  ever  dreams  that  the  conversation  of  the  wise  is  any  less 
entertaining,  or  less  instructive,  or  less  profitable  now  than  it  was 
before  men  studied  philology. 

As  I  understand  Agassiz,  it  is  not  because  natural  history  is 
a  language,  that  he  holds  it  to  be  intended ;  but  because  it  is 
delightful  to  listen  to  the  language  of  nature,  and  because  it 
abounds  in  beneficial  instruction  for  mankind. 

Is  it  not  because  this  is  true  that  the  man  of  science  holds  his 
pursuit  to  be  both  the  first  and  highest  of  duties  and  the  greatest 
of  all  pleasures  ? 

"  And  if,"  says  Agassiz,  "  this  is  indeed  so,  do  we  not  find  in  this 
adaptability  of   the    human    intellect   to   the   facts   of   creation,    by 


324  THE  FOUNDATIONS  OF  ZOOLOGY 

which  we  become  instinctively,  and,  as  I  have  said,  unconsciously, 
the  translators  of  the  thoughts  of  God,  the  most  conclusive  proof 
of  our  affinity  with  the  Divine  Mind  ?  and  is  not  this  intellectual 
and  spiritual  connection  with  the  Almighty  worthy  our  deepest 
consideration  ? 

"  If  there  is  any  truth  in  the  belief  that  man  is  made  in  the 
image  of  God,  it  is  surely  not  amiss  for  the  philosopher  to  en- 
deavor, by  the  study  of  his  own  mental  operations,  to  approximate 
the  workings  of  the  Divine  Reason,  learning,  from  the  nature  of 
his  own  mind,  better  to  understand  the  Infinite  Intellect  from 
which  it  is  derived.  Such  a  suggestion  may,  at  first  sight,  appear 
irreverent.  But,  which  is  the  truly  humble  .'*  He  who,  penetrating 
into  the  secrets  of  creation,  arranges  them  under  a  formula  which 
he  proudly  calls  his  scientific  system }  or  he  who,  in  the  same 
pursuit,  recognizes  his  glorious  affinity  with  the  Creator,  and,  in 
deepest  gratitude  for  so  sublime  a  birthright,  strives  to  be  the 
faithful  interpreter  of  that  Divine  Intellect  with  whom  he  is  per- 
mitted, nay,  with  whom  he  is  intended,  according  to  the  laws  of 
his  being,  to  enter  into  communion  .-* " 

I  find  no  reference  to  Berkeley  in  the  Essay  on  Classification, 
although  the  Swiss  naturalist  would  have  found  much  to  interest 
him  in  the  works  of  the  Irish  bishop;  for  they  have  much  in 
common,  and  the  study  of  Berkeley  might  have  taught  Agassiz 
that  there  is  no  necessary  antagonism  between  mechanical  concep- 
tions of  nature  and  belief  that  nature  is  intended;  for  Berkeley  holds 
that  ^'  all-  the  phenomena  in  nature  are  produced  by  motion." 

While  something  like  that  of  Agassiz,  Berkeley's  reasoning  com- 
pares with  it  much  as  Agassiz's  reasoning  itself  compares  with 
that  of  Paley  and  the  authors  of  Bridgewater  Treatises. 

Berkeley  neither  reasons  like  Paley  from  the  contrivances  in 
living  beings,  nor  like  Agassiz  from  the  relations  of  living  things  to 
each  other  and  to  the  world  about  them,  but  from  nature  in  itself, 
telling  us  that  "  setting  aside  all  help  of  astronomy  and  natural 
phylosophy,  all  contemplation  of  the  contrivance,  order,  and  adjust- 
ment of  things,"  there  is  a  teleological  argument  which  is  "inde- 
pendent of  research  into  the  sciences." 

Even   Berkeley  himself  is  not  always  consistent,  however;    for 


LOUIS  AGASSIZ  AND   GEORGE  BERKELEY  325 

after  giving,  in  the  second  dialogue  between  Hylas  and  Philonous, 
his  reasons  for  believing  that  "  the  Supreme,  unlimited  Agent  useth 
no  tool  or  instrument  at  all,"  and  after  pointing  out  that  we 
cannot  "suppose  that  an  all-perfect  Spirit  should  need  an  instru- 
ment, or,  not  needing  it,  make  use  of  it,"  he  tells  us  in  "  Siris," 
(151-161)  that  "the  mind  presiding  in  the  world"  does  use  instru- 
ments, and  that  the  fitness  of  nature  for  the  needs  of  man  is 
evidence  of  contrivance,  or  the  use  of  means  for  the  attainment 
of  ends ;  for  he  holds  that  the  mechanism  of  nature  is  "  necessary 
to  assist  the  governed " ;  and  he  tells  us  it  is  maintained  /;/  order 
that  intelligent  beings  may  exist,  although  one  must  ask  whether 
proof  that  nature  is  useful  is  proof  that  it  is  necessary. 

"  Without  a  regular  course,"  says  Berkeley,  "  nature  could  never 
be  understood ;  mankind  must  be  always  at  a  loss,  not  knowing 
what  to  expect,  or  how  to  govern  themselves,  or  direct  their  actions 
for  the  obtaining  of  any  end."  As  a  matter  of  fact,  we  do  have 
practical  confidence  in  the  stability  of  the  order  of  nature,  and 
we  do  not  find  ourselves  at  a  loss  except  through  ignorance,  al- 
though we  do  not  know  whether  we  shall  be  alive  an  hour  hence. 
We  know  what  we  expect,  although  nothing  is  more  certain  than 
that  we  never  know  whether  what  we  expect  will  happen.  We 
do  govern  ourselves,  and  we  have,  in  the  past,  been  able  to  direct 
our  actions  for  the  attainment  of  ends,  so  that  on  the  whole  our 
ends  have  been  attained  when  we  have  made  no  mistakes ;  for 
whether  the  mechanism  of  nature  is  necessary  or  not,  our  confi- 
dence in  its  stability  has  not,  so  far,  disappointed  any  expectations 
that  were  reasonable  and  well  founded. 

It  is  not  even  necessary  that  we  should  know  the  value  of  re- 
sponse to  the  order  of  nature  in  order  to  bring  about  beneficial 
ends,  for  many  of  our  most  important  responses  take  place  in 
unconsciousness.  The  value  of  our  circulation  did  not  begin  with 
Harvey;  nor  need  one  know  anything  about  the  chemistry  of 
respiration  or  nutrition  in  order  to  profit  by  it. 

"  Unconscious  activity,"  says  Holmes,  "  is  the  rule  with  the 
actions  most  important  to  life.  The  lout  who  lies  stretched  on 
the  tavern-bench,  with  just  mental  activity  enough  to  keep  his 
pipe  from  going  out,  is  the  unconscious  tenant  of  a  laboratory 
where  such  combinations  are  constantlv  being  made  as  never  Wohlcr 


326  THE  FOUNDATION'S  OF  ZOOLOGY 

or  Berthelot  could  put  together ;  where  such  fabrics  are  woven, 
such  colors  dyed,  such  a  commerce  carried  on  with  the  elements 
and  forces  of  the  outer  universe,  that  the  industries  of  all  the  fac- 
tories and  trading  establishments  in  the  world  are  mere  indolence 
and  awkwardness  and  unproductiveness  compared  with  the  mi- 
raculous activities  of  which  his  lazy  bulk  is  the  unheeding  centre." 

"  We  wish  to  remember  something  in  the  course  of  conversation. 
No  effort  of  the  will  can  reach  it ;  but  we  say,  '  Wait  a  little,  and 
it  will  come  to  me,'  and  go  on  talking.  Presently,  perhaps  some 
minutes  later,  the  idea  we  are  in  search  of  comes  all  at  once  into 
the  mind,  delivered  like  a  prepaid  bundle,  laid  at  the  door  of  con- 
sciousness like  a  foundling  in  a  basket." 

"  There  are  thoughts  that  never  emerge  into  consciousness  which 
yet  make  their  influence  felt  among  the  perceptible  mental  cur- 
rents, just  as  the  unseen  planets  sway  the  movements  of  those 
which  are  watched  and  mapped  by  the  astronomers.  Old  prej- 
udices, that  are  ashamed  to  confess  themselves,  nudge  our  talking 
thoughts  to  utter  their  magisterial  veto.  The  more  we  examine 
the  mechanism  of  thought,  the  more  we  shall  see  that  the  automatic 
unconscious  action  of  the  mind  enters  largely  into  all  its  processes. 
Our  definite  ideas  are  stepping-stones ;  how  we  get  from  one  to 
the  other  we  do  not  know ;  something  carries  us,  we  do  not  take 
the  step. 

"  It  is  not  strange  that  remembered  ideas  should  often  take 
advantage  of  the  crowd  of  thoughts,  and  smuggle  themselves  in  as 
original.  Honest  thinkers  are  always  stealing  unconsciously  from 
each  other.  Our  minds  are  full  of  waifs  and  estrays  which  we 
think  are  our  own.  Innocent  plagiarism  turns  up  everywhere. 
Our  best  musical  critic  tells  me  a  few  notes  from  the  air  of  '  Shoo 
Fly '  are  borrowed  from  a  movement  in  one  of  the  magnificent 
harmonies  of  Beethoven."  ^ 

While  it  is  as  a  metaphysician  that  Berkeley  is  best  known  in 
our  day,  no  one  can  read  any  of  his  works  without  discovering  that 
their  purpose  is  practical  and  not  speculative.  The  avowed  object 
of  "  Siris  "  is  to  show  why  tar  water  must  be  a  "  catholicon  "  ;  but  the 
whole  aim  of  his  other  works  is  to  show  that  immediately  and  in 
itself  natural  knowledge  is  a  language  by  which  we  are  instructed ; 

^  Holmes,  "  Mechanism  in  Thought  and  Morals." 


LOUIS  AGASSIZ  AND    GEORGE  BERKELEY  327 

and  that  no  one  who  is  convinced  that  natural  knowledge  is  useful 
need  ask  whether  nature  is  intended,  with  any  doubt  of  the  answer. 

He  holds,  indeed,  that  we  cannot  be  sure  that  nature  is  a  lan- 
guage unless  we  are  convinced  that  it  is  nothing  but  a  language ; 
for  while  his  idealistic  philosophy  is  only  a  means  to  an  end,  he 
holds  it  essential  for  the  attainment  of  this  end;  although  the 
modern  zoologist  must  ask  whether  he  is  right,  or  whether,  on  the 
contrary,  one  who  does  not  know  what  the  relation  between  mind 
and  matter  is  may  not  agree  with  him  that  nature  is  a  language. 

Berkeley's  teleological  argument  is  set  forth  in  all  his  writings ; 
but  it  is,  perhaps,  less  complicated  by  metaphysics  in  the  fourth 
dialogue  with  Alciphron  than  anywhere  else. 

Alciphron  asserts  that  no  evidence  which  is  not  as  conclusive 
as  that  which  proves  the  existence  of  his  fellow-men  will  convince 
him  of  the  existence  of  a  God. 

He  says:  "Nothing  so  much  convinces  me  of  the  existence  of 
another  person  as  his  speaking  to  me.  It  is  my  hearing  you  talk 
that,  in  strict  and  philosophical  truth,  is  to  me  the  best  argument 
for  your  being.  And  this  is  a  peculiar  argument,  inapplicable  to 
your  purpose ;  for  you  will  not,  I  suppose,  pretend  that  God  speaks 
to  man  in  the  same  clear  and  sensible  manner  as  one  man  doth 
to  another.? 

"  What  I  mean,  is  not  the  sound  of  speech  merely  as  such,  but 
the  arbitrary  use  of  sensible  signs,  which  have  no  similitude  or 
necessary  connection  with  the  things  signified ;  so  as  by  the  appo- 
site management  of  them  to  suggest  and  exhibit  to  my  mind  an 
endless  variety  of  things  differing  in  nature,  time,  and  place  ;  thereby 
informing  me,  entertaining  me,  and  directing  me  how  to  act,  not 
only  with  regard  to  things  near  and  present,  but  also  with  regard 
to  things  distant  and  future.  No  matter  whether  these  sounds  are 
pronounced  or  written  ;  whether  they  enter  by  the  eye  or  ear  ;  they 
have  the  same  use,  and  are  equally  proofs  of  an  intelligent,  thinking, 
designing  cause." 

"  But  if  it  should  appear  that  God  really  speaks  to  men,  would 
this  content  you  ?  "  asks  Euphranor. 

"  I  am  for  admitting  no  inward  speech,  no  holy  instincts  or  sug- 
gestions of  light  and  spirit,"  answers  Alciphron.  "  All  that,  you 
must  know,  passeth  with  men  of  sense  for  nothing.     If  you  do  not 


328  THE  FOUNDATIONS   OF  ZOOLOGY 

make  it  plain  to  me  that  God  speaks  to  me  by  outward  sensible 
signs,  of  such  sort  and  in  such  manner  as  I  have  defined,  you  do 
nothing." 

Euphranor  now  asks  Alciphron  to  consider  natural  knowledge. 
He  points  out,  in  effect,  that  what  we  call  the  laws  of  nature  are 
no  more  than  generalizations,  based  on  experience,  and  that  we 
fail  to  find  in  nature  any  a  priori  demonstration  of  any  one  of 
them,  any  evidence  that  they  are  necessary,  any  reason  why  they 
must  hold  good.  He  shows  that  all  natural  knowledge  is  know- 
ledge of  appearances  or  phenomena,  or  ideas,  as  he  prefers  to  call 
them ;  and  that,  while  the  events  that  make  up  the  order  of  nature 
are  vulgarly  considered  under  the  relation  of  cause  and  effect, 
they  are,  in  strict  and  philosophic  truth,  only  known  to  be  related 
as  the  sign  and  the  thing  signified.  He  shows,  in  a  word,  that, 
so  far  at  least  as  we  are  concerned  with  them  or  know  anything 
about  them,   "  natural  phenomena  are  only  natural  appearances'' 

Men  of  science  have  themselves  learned  to  reflect  upon  natural 
knowledge  since  Berkeley's  day ;  and  as  they  are  now  practically 
of  his  way  of  thinking  on  this  matter,  it  is  no  longer  necessary  to 
review,  in  detail,  his  demonstration  that,  behind  phenomena,  we 
discover  in  nature  nothing  except  the  farther  truth  that  all  natural 
knowledge  is  useful  and  instructive  and  pleasant  to  learn  —  a  truth 
which  the  modern  man  of  science  should  be  the  last  to  question. 

Berkeley  points  out  that,  these  things  being  admitted,  it  follows 
according  to  Alciphron's  definition,  that  nature  is  a  language ;  al- 
though we  learn  the  language  of  nature  so  easily  and  gradually 
that  we  are  unconscious  of  the  act. 

"  If  we  have  all  been  practising  this  language,  ever  since  our 
first  entrance  into  the  world,  it  doth  not  seem  to  me  at  all  strange 
that  men  should  not  be  aware  they  had  learned  a  language  begun 
so  early  and  practised  so  constantly.  And  if  we  also  consider 
that  it  is  the  same  throughout  the  world,  and  not,  like  other  lan- 
guages, differing  in  different  places,  it  will  not  seem  unaccoun- 
table that  men  should  mistake  the  connection  between  the  proper 
objects  of  sight  and  the  things  signified  by  them  to  be  founded 
in  necessary  relation  or  likeness." 

If  Berkeley  had  been  a  modern  zoologist,  he  would,  no  doubt, 
have  made  this  assertion  still  stronger;    by  pointing   out   that   the 


LOUIS  AGASSIZ  AND    GEORGE  BERKELEY  329 

whole  history  of  life  is  a  history  of  the  acquisition  of  the  lan- 
guage of  nature;  for  each  stimulus  to  a  vital  act  is  a  sign  with  a 
significance;  and  we  have  seen,  page  63,  that  a  living  thing  is 
a  being  which,  when  affected  by  a  stimulus,  prepares  itself  for 
the  significance,  of  which,  in  course  of  nature,  it  is  the  sign. 
Berkeley  himself  saw  clearly,  and  he  tells  us  in  many  places, 
that  it  is  not  necessary  that  the  language  of  nature  be  intelli- 
gently apprehended  in  order  to  be  instructive,  for  human  speech 
is  often  used  to  warn  or  to  excite  or  to  please,  rather  than  to 
call  up  mental  images ;  and  one  may  be  sure  that  all  living  things 
respond  to  the  language  of  nature  to  their  advantage,  without 
knowing  whether  they  consciously  apprehend  the  benefit  of  re- 
sponse or  not. 

"It  may  also  be  worth  while,"  says  Berkeley,  "to  observe  that 
signs,  being  little  considered  in  themselves,  or  for  their  own  sake, 
but  only  in  their  relative  capacity,  and  for  the  sake  of  those 
things  whereof  they  are  signs,  it  comes  to  pass  that  the  mind 
overlooks  them,  so  as  to  carry  its  attention  immediately  on  to  the 
thing  signified.  Thus,  for  example,  in  reading  we  run  over  the 
characters  with  the  slightest  regard,  and  pass  on  to  the  meaning. 
Hence  it  is  frequent  for  men  to  say  they  see  words,  and  notions, 
and  things  in  reading  a  book ;  whereas  in  strictness  they  see  only 
the  characters  which  suggest  words,  notions,  and  things.  And  by 
parity  of  reason,  may  we  not  suppose  that  men,  not  resting  in, 
but  overlooking  the  immediate  and  proper  objects  of  sight,  as  in 
their  own  nature  of  small  moment,  carry  their  attention  onward 
to  the  very  things  signified,  and  talk  as  if  they  saw  the  secondary 
objects,  which,  in  truth  and  strictness,  are  not  seen,  but  only 
suggested  and  apprehended  by  means  of  the  proper  objects  of 
sight,  which  alone  are  seen." 

"  But,  to  cut  short  this  chicane,"  says  Alciphron,  "  I  propound 
it  fairly  to  your  own  conscience,  whether  you  really  think  God 
Himself  speaks  every  day  and  in  every  place  to  the  eyes  of  all 
men." 

"This  is  really  and  in  truth  my  opinion,"  answers  Euphranor, 
"  and  it  should  be  yours  too,  if  you  are  consistent  with  yourself 
and  abide  by  your  own  definition  of  language.  Since  you  can- 
not deny  that  the  great  Mover  and  Author  of  nature    constantly 


330  THE  FOUNDATIONS   OF  ZOOLOGY 

explaineth  Himself  to  the  eyes  of  men  by  the  sensible  interven- 
tion of  arbitrary  signs,  which  have  no  similitude  or  necessary 
connection  with  the  things  signified ;  so  as,  by  compounding  and 
composing  them,  to  suggest  and  exhibit  an  endless  variety  of 
objects,  differing  in  nature,  time,  and  place;  thereby  informing 
and  directing  men  how  to  act  with  respect  to  things  distant  and 
future  as  well  as  near  and  present. 

"  In  consequence,  I  say,  of  your  own  sentiments  and  conces- 
sions, you  have  as  much  reason  to  think  the  Universal  Agent 
or  God  speaks  to  your  eyes,  as  you  can  have  for  thinking  any 
particular  person  speaks  to  your  ears. 

**  You,  it  seems,  stare  to  find  God  is  not  far  from  every  one  of 
us ;  and  that  in  Him  we  live,  and  move,  and  have  our  being.  You, 
who  in  the  beginning  of  this  morning's  conference,  thought  it 
strange  God  should  leave  Himself  without  a  witness,  do  now 
think  it  strange  the  witness  should  be  so  full  and  clear." 

The  modern  philologist  knows  that  the  relation  between  words 
and  the  things  they  signify  is  orderly  and  natural ;  for  he  studies, 
by  scientific  methods,  the  natural  laws  shown  by  the  life  and 
growth  of  language ;  but  I  am  as  unable  to  see  why  one  must 
know  that  the  relation  between  natural  signs  and  their  signifi- 
cance is  "arbitrary,"  before  he  admits  the  reality  of  the  language 
of  nature,  as  I  am  to  see  how  the  scientific  study  of  language 
shows  that  discourse  with  the  wise  is  not  useful  and  instructive 
and  entertaining. 

In  fact,  Berkeley,  who  here  asserts  that  the  relation  is  "arbi- 
trary," tells  us,  in  "  Siris "  that  it  is  "necessary."  I  am  quite 
unable  to  see  how  or  why  his  reasoning  should  seem  more  con- 
vincing to  an  idealist  than  to  one  who  is  "of  a  vulgar  cast,"  and 
simple  enough  to  take  things  as  he  finds  them. 

Berkeley,  the  idealist,  says  nature  is  nothing  but  a  language, 
but   I   fail  to  see  how  his  reasoning  turns  on  this,  "nothing  but." 

Berkeley,  the  realist,  tells  us  the  language  of  nature  "is  neces- 
sary to  assist  the  governed  "  ;  but  if  we  are  sure  nature  is  useful, 
why  should  we  care  whether  it,  or  any  part  of  it,  is  necessary, 
or  unnecessary .-' 

The  eternal  paradox  about  necessity  and  freedom  has  no  mean- 
ing to  the  humble-minded  zoologist,  who  admits  his  accountability, 


LOUIS  AGASSIZ  AND   GEORGE  BERKELEY  33 1 

even  if  he  knows  nothing  about  absolute  necessity,  nothing  about 
arbitrary  liberty;  and  is  quite  content  to  leave  to  Milton's  fiends 
the  discussion  of  "  Fix'd  fate,  free  will,  foreknowledge  absolute." 
This  itself  seems  to  me  a  great  gain,  and  a  prodigious  conserva- 
tion of  energy,  worth   no  little   hard  work. 

May  not  one  who  is  convinced  with  Berkeley  that  nature  is  a 
language,  find  reason  to  doubt  whether  he  has  correctly  and  fully 
understood  what  he  has  heard,  or  whether  he  will  be  able  to  under- 
stand what  he  may  still  hear  .-• 

While  the  Darwinian,  like  every  other  thoughtful  student, 
admits  that  the  adjustments  of  living  things  to  the  external  world 
are  useful,  he  asks  whether,  quite  apart  from  all  question  of  pur- 
pose or  intention,  these  beneficial  adjustments  may  not  themselves 
be  part  of  the  mechanism  of  nature.  He  asks  whether  man  may 
not  have  survived  because  he  fits  nature,  and  whether  another  line 
might  not  have  survived  if  nature  had  been  different. 

As  he  knows  no  reason  in  the  nature  of  things  why  all  should 
not  come  to  an  end  this  instant,  he  is  unable  to  discover  any  assur- 
ance of  stability  in  nature  itself;  and  if  he  is  to  find  any  such 
assurance  anywhere,  how  is  he  helped  by  the  assertion  that  "  in 
the  government  of  the  world  physical  agents,  or  mechanical,  or 
secondary  causes,  or  instruments,  are  necessary,"  either  to  assist 
the  governed  or  for  anything  else  t 

May  not  the  Darwinian  ask  whether  our  confidence  in  the 
stability  of  nature  may  not  be  equivalent  to,  and  whether  it  can 
ever  exceed,  our  confidence  in  the  continuity  of  life  .-• 

"That  a  thing  should  be  really  perceived  by  my  senses,  and 
at  the  same  time  not  really  exist,  is  to  me  a  plain  contradiction," 
says  Berkeley,  "since  I  cannot  prescind  or  abstract,  even  in 
thought,  the  existence  of  a  sensible  thing  from  its  being  perceived. 
I  might  as  well  doubt  of  my  own  being  as  of  the  being  of  those 
things  I  see  and  feel." 

"  If  a  man  should  give  me  arguments  that  I  do  not  see," 
says  Holmes,  quoting  from  Johnson,  "though  I  could  not  answer 
them,  should  I  believe  I  do  not  see .'  " 

May  not  one  who  cannot  doubt  the  reality  of  the  things  he 
sees  and  feels,  ask  whether  all  the  things  he  sees  and  feels  tell 
him  what    to    expect,  or    how    to    govern    himself    and    direct    his 


332  THE  FOUNDATIONS  OF  ZOOLOGY 

actions  for  the  attainment  of  ends  ?  May  not  some  of  the  things 
we  see  and  feel  be  illusions  ?  He  who  is  giddy  feels  the  world 
turn  round.  One  who  has  lost  his  legs  may  suffer  from  cold  feet. 
We  see  the  sun  rise  in  the  morning  and  run  his  course  through 
the  sky  until  the  evening.  From  the  windows  of  the  moving 
train  we  see  the  ranks  of  corn  circle  round  the  middle  distance. 
The  skilful  dramatist  makes  us  feel  all  the  emotions  and  impulses 
a  real  tragedy  would  excite. 

While  all  the  things  we  see  and  feel  are,  no  doubt,  equally 
real,  they  are  not  all  real  in  the  same  way ;  for  while  it  is  true 
that  we  cannot  doubt  the  evidence  of  our  senses,  familiar  experi- 
ence teaches  that  our  senses  are  often  deceptive,  since  their  evi- 
dence stands  in  need  of  continual  correction  ;  for  delusion  and 
hallucination  and  error  are,  unfortunately,  as  real  as  truth. 

The  most  practical  and  important  question  which  rational  living 
beings  can  ask  is  how  we  may  distinguish  truth  from  error,  in 
order  that  we  may  think  wisely,  and  be  sure  about  our  actions, 
and  rightly  order  our  lives ;  and  the  greatest  service  of  Charles 
Darwin  to  the  intellectual  life  of  mankind  is  that  he  has  led  us 
to  ask  whether  we  may  not  some  time  find  a  mechanical  explana- 
tion of  that  rational  judgment  which  is  innate  in  intelligent  human 
beings ;  whether  this  may  not  itself  be  part  of  the  physical 
order  of  nature ;  whether  language  itself,  even  the  most  rational 
discourse,  may  not  be  a  natural  phenomenon,  which  lies  entirely 
within  the  limits  of  physical  causation;  whether  proof  that  nature 
is  a  language  is  proof  that  this  language  is  supernatural. 

He  asks  whether  those  judgments  which  we  call  errors  may 
not  be  the  ones  which  lead  us  into  danger  and  tend  to  our  physi- 
cal destruction,  and  whether  it  may  not  be  because  a  judgment  has 
proved  beneficial  in  the  struggle  for  existence  that  we  call  it  true. 

On  the  other  hand,  he  does  not  forget  that  hallucinations, 
even  those  of  the  insane,  are  themselves  truths  of  nature,  which, 
wisely  interpreted,  may  help  the  physician  to  minister  to  a  mind 
diseased.  He  therefore  asks  whether  hallucinations  are  not  use- 
ful in  the  same  way  that  all  natural  knowledge  is  useful ;  whether 
illusions  and  errors  are  not  truths  misunderstood ;  whether  they 
are  exceptions  to  the  rule  that  all  natural  knowledge  is  useful 
and  instructive  to  all  who  hear  aright  the  language  of  nature. 


LOUIS  AGASSIZ  AND   GEORGE  BERKELEY  333 

If  future  discovery  should  demonstrate  that  Darwin  is  right, if 

the  value  of  our  rational  minds  should  prove  mechanical  and  no 
more  than  might  have  been  expected  from  our  structure  and  history, 
—  how  could  this  prove  that  their  value  is  not  real  value?  While 
individuals  survive  or  fall  in  the  struggle  for  existence,  this  struggle 
produces  nothing,  for  natural  selection,  like  all  natural  laws,  is  a 
generalization  from  experience,  and  not  an  efficient  cause. 

While  no  one  can  doubt  his  senses,  we  do  continually  doubt  or 
question  the  value  of  our  sensations;  for  if  the  Lamarckian  holds 
that  knowledge  is  produced  by  experience,  the  Darwinian  asks 
whether  what  we  call  the  evidence  of  our  senses  is  anything  more 
than  a  stimulus  in  the  presence  of  which  knowledge  arises  in  the 
mind;   anything  more  than  the  condition  or  occasion  of  knowledge. 

"We  know  a  thing  when  we  understand  it;  and  we  understand 
it  when  we  can  interpret,  or  tell  what  it  signifies.  Strictly,  the 
sense  knows  nothing.  We  perceive,  indeed,  sounds  by  hearing  and 
characters  by  sight.  After  the  same  manner,  the  phenomena  of 
nature  are  alike  visible  to  all ;  but  all  have  not  alike  learned  the 
connection  of  natural  things,  or  understand  what  they  signify,  or 
know  how  to  vaticinate  by  them.  There  is  no  question,  saith 
Socrates,  concerning  that  which  is  agreeable  to  each  person ;  but 
concerning  what  will  in  time  to  come  be  agreeable,  of  which  all 
men  are  not  equal  judges.  He  who  foreknoweth  what  will  be  in 
every  kind  is  the  wisest.  According  to  Socrates  you  and  the  cook 
may  judge  of  the  dish  on  the  table  equally  well,  but  while  the  dish 
is  making,  the  cook  can  better  foretell  what  will  ensue  from  this 
or  that  manner  of  composing  it.  Nor  is  this  manner  of  reasoning 
confined  only  to  morals  and  politics;  but  extends  also  to  the  natural 
sciences. 

"  As  the  natural  connexion  of  signs  with  the  things  signified 
is  regular  and  constant,  it  forms  a  sort  of  rational  discourse. 
Therefore  the  phenomena  of  nature,  which  strike  on  the  senses, 
and  are  understood  by  the  mind,  do  form  not  only  a  magnificent 
spectacle,  but  also  a  most  coherent,  entertaining,  and  instructive 
Discourse;  and  to  effect  this,  they  are  conducted,  adjusted,  and 
ranged  by  the  greatest  wisdom.  This  Language  or  Discourse  is 
studied  with  different  attention  and  interpreted  with  different 
degrees  of  skill.      But   so  far  as  men   have  studied  and   remarked 


334  THE  FOUNDATIONS  OF  ZOOLOGY 

its  rules,  and  can  interpret  right,  they  may  be  said  to  be  knowing 
in  nature."  ^ 

I  see  no  incompatibiUty  between  Darwin's  view  of  fitness  and 
belief  that  nature  is  a  language  and  that  mechanical  principles  "may 
be  very  naturally  explained,  and  have  a  very  proper  and  obvious 
use  assigned  to  them  when  they  are  considered  only  as  marks  or 
signs  for  our  information  " ;  although  I  cannot  see  how  this  proves 
that  they  are  necessary  for  this  purpose,  or  that  this  is  their  only 
or  chief  use;  for  if  natural  selection  casts  doubt  on  the  opinion  that 
the  language  of  nature  is  an  instrument,  I  fail  to  see  how  it  shows 
that  nature  is  not  a  language. 

Since  the  zoologist  must  ask  whether  the  realistic  teleology  of 
Berkeley's  "  Siris  "  furnishes  any  evidence  of  the  use  of  instruments 
which  is  not  itself  instrumental  or  mechanical,  is  it  not  exposed 
to  all  the  difficulty  which  we  find  in  all  instrumental  teleology } 
It  is,  assuredly,  very  different  from  that  earlier  teleology  which  is 
said  to  be  so  independent  of  "  any  laborious  research  into  the 
sciences "  that  we  are  told  one  need  only  open  his  eyes  to  see  it. 

"  In  vain  do  we  extend  our  view  into  the  heavens  and  pry 
into  the  entrails  of  the  earth,  in  vain  do  we  consult  the  writings 
of  learned  men,  and  trace  the  dark  footsteps  of  antiquity  —  we 
need  only  draw  the  curtain  of  words  to  behold  the  fairest  tree 
of  knowledge,  whose  fruit  is  excellent,  and  within  the  reach  of 
our  hand. 

"That,  setting  aside  all  help  of  astronomy  and  natural  philos- 
ophy, all  contemplation  of  the  contrivance,  order,  and  adjustment 
of  things,  an  infinite  mind  should  be  necessarily  [logically]  inferred 
from  the  bare  existence  of  the  sensible  world,  is  an  advantage  to 
those  only  who  have  made  this  easy  reflection  :  that  the  sensible 
world  is  "  instructive,  and  etitertaining,  and  delightful. 

May  not  one  who,  being  no  philosopher,  has  no  opinion,  either 
positive  or  negative,  about  any  physical  universe  except  that  which 
he  perceives,  or  has  perceived,  or  might  perceive  if  he  hnd  time 
and  opportunity,  by  means  of  his  senses,  make  this  "  easy  reflec- 
tion "  just  as  easily  as  one  who  believes  nature  is  necessary,  either 
to  assist  the  governed  or  for  any  other  purpose .'' 

The  same  Berkeley  who  was  led  into  the  philosophy  of  evolution 

^  Berkeley,  "  Siris,"  253,  254. 


LOUIS  AGASSIZ  AND   GEORGE  BERKELEY  335 

in  his  old  age  by  his  wish  to  find  in  nature  some  reason  why  tar 
water  must  be  a  universal  panacea,  seems  to  have  made  this  easy 
reflection  just  as  easily  as  the  young  idealist  of  the  dialogues 
•with  Hylas.  May  we  not  therefore  ask  whether  one  need  be  an 
idealist  to  find  evidence  that  nature  is  a  language  ?  May  not 
this  evidence  be  just  as  clear  to  one  who  is  no  philosopher  as  if 
he  were  an  idealist,  or  a  realist,  or  a  nominalist,  or  a  materialist, 
or  a  monist,  or  an  evolutionist,  or  a  disciple  of  any  other  school 
in  the  great  college  of  scholastic  philosophy  ? 

"  It  is  for  me  a  sufficient  reason  not  to  believe  the  existence 
of  anything,  if  I  see  no  reason  for  believing  it,"  says  Berkeley ; 
and  a  student  of  science  who  is  "  of  a  vulgar  cast "  and  simple 
enough  to  believe  his  own  senses  and  leave  things  as  he  finds 
them,  may  find  as  much  reason  as  an  idealist  for  refusing  to 
believe  that  nature  is  necessary  ;  nor  need  he  be  at  all  disturbed 
if  some  should  call  him  an  agnostic. 

As  I  understand  Berkeley,  it  is  not  because  nature  is  orderly, 
but  because  the  order  of  nature  is  useful,  and  instructive,  and 
full  of  delights  for  living  things,  that  he  holds  it  to  be  a  language. 
Even  if  the  Darwinian  asks  whether  the  order  of  nature  may  not 
te  mechanical,  and  explicable  by  physical  science,  I  fail  to  see 
why  he  should  challenge  Berkeley's  belief  that  it  is  intended, 
unless  he  doubts  whether  response  to  the  order  of  nature  is 
useful  and  profitable  and  delightful. 

Does  any  man  of  science  doubt  whether  the  words  "  language 
of  nature"  and  "interpretation  of  nature"  are  used  with  clear, 
intelligible  meaning  .-*  Is  not  the  question  whether  nature  is  a 
language  which  we  learn  to  our  delight  and  profit  and  instruction 
•quite  a  different  matter  from  the  question  whether  the  language 
of  nature  is  necessary  or  unnecessary .'' 

May  not  one  who  does  not  know  what  the  relation  between 
-mind  and  matter  is,  one  who  is  unable  to  find  his  way  through 
the  perplexities  which  schoolmen  and  metaphysicians  and  theolo- 
gians and  other  "philosophers"  have  thrown  around  the  question 
whether  the  language  of  nature  is  necessary  or  not,  still  find  a 
plain  and  easy  answer  to  the  simpler  question  whether  nature  is 
a  language  by  which  we  are  entertained  and  instructed  ? 

The  student  of  science  should  be  the  last  to  doubt  this  possi- 


336  THE  FOUNDATIONS  OF  ZOOLOGY 

bility  even  for  an  instant ;  for  he  asserts  that  it  is  because  exact 
science  does  help  one  to  walk  with  sure  feet  where  others  grope 
and  stumble,  that  the  promotion  of  natural  knowledge  is  the  first 
and  highest  of  duties.  How  can  one  who  knows  that  natural 
knowledge  does  correct  our  judgment  and  help  us  to  avoid  the 
dangers  that  beset  and  destroy  the  ignorant,  ask  whether  nature 
is  a  language  profitable  to  direct  ? 

"  I  sometimes  feel,"  says  Holmes,  "  as  if  I  should  like  to  found 
a  school  to  teach  the  ignorance  of  what  people  do  not  want  to 
know." 

If  we  are  sure  nature  is  useful,  need  any  one  care  to  ask 
whether  it  is  necessary  or  arbitrary  ?  "  What  have  you  to  do 
with  liberty  and  necessity .''  or  what  more  than  to  hold  your  tongue 
about  it .'' "  asks  Johnson  of  Boswell. 

"  The  attitude  of  Modern  Science  is  erect,  her  aspect  serene, 
her  determination  inexorable,  her  onward  movement  unflinching, 
because  she  believes  herself,  in  the  order  of  Providence,  the  true 
successor  of  those  men  of  old  who  brought  down  the  light  of 
heaven  to  men.  Humility  may  be  taken  for  granted  as  existing 
in  every  sane  human  being ;  but  it  may  be  that  it  most  truly 
manifests  itself  to-day  in  the  readiness  with  which  we  bow  to  new 
truths  as  they  come  from  the  scholars,  the  teachers,  to  whom  the 
inspiration  of  the  Almighty  giveth  understanding."  ^ 

Paley  sometimes  argues  that  even  if  the  finder  of  the  watch 
were  without  knowledge  of  watchmakers,  or  other  human  con- 
trivers, proof  of  design  is  to  be  found  in  the  adjustment  between 
its  movements  and  those  of  the  earth ;  while  it  is  equally  clear 
that,  in  other  passages,  he  bases  his  argument  on  the  analogy 
between  the  mechanism  of  nature  and  the  works  of  human 
mechanics.  After  comparing  the  eye  with  a  telescope,  he  asks : 
"What  could  a  mathematical  instrument  maker  have  done  more 
to  show  his  knowledge  of  his  principles,  his  application  of  that 
knowledge,  his  suiting  of  his  means  to  his  ends.''"  On  the  other 
hand,  his  opening  passage,  in  which  his  thesis  is  developed, 
makes  no  reference  to  human  contrivers.  "  Suppose  I  found 
a   watch    upon    the    ground,    and   it   should    be    inquired    how   the 

1  Holmes,  "  Mechanism  in  Thought  and  Morals." 


LOUIS  AGASSIZ  AND   GEORGE  BERKELEY  337 

watch  happened  to  be  in  that  place,  I  should  hardly  think  of  the 
answer  which  I  had  before  given.  Yet  why  should  not  this 
answer  serve  for  the  watch,  as  well  as  for  the  stone  ?  Why  is  it 
not  as  admissible  in  the  second  case  as  in  the  first?  For  this 
reason,  and  for  no  other,  viz.  that  when  we  come  to  inspect  the 
watch  we  perceive  (what  we  could  not  discover  in  the  stone) 
that  its  several  parts  are  framed  and  put  together  for  a  purpose, 
e.g.  that  they  are  so  formed  and  adjusted  as  to  produce  motion, 
and  that  motion  so  regulated  as  to  point  out  the  hour  of  the 
day." 

Whether  it  is  or  is  not  possible  to  prove  intention  without 
proving  contrivance,  I  do  not  believe  one  can  read  a  dozen  pages 
of  Paley  or  of  any  other  English  writer  on  natural  theology, 
without  finding  that  they  fail  to  draw  any  such  distinction ;  and 
while  the  question  what  they  believed  may  have  only  an  histori- 
cal interest,  it  is  important  to  note  that  the  point  of  view  has 
changed. 

We  have  seen  that,  like  Paley,  even  Berkeley  is  not  always 
consistent ;  but  as  his  earlier  works  are  by  far  the  clearest  and 
at  the  same  time  the  most  profound  of  all  the  writings  on  natural 
theology,  I  have  tried  to  set  forth  his  reasoning  in  the  clearest 
way  I  can  command  in  the  space  at  my  disposal ;  although  I 
hope  no  one  who  does  not  know  Berkeley  at  first  hand  will  be 
contented  with  my  summary ;  for  his  beautiful  essays  and  dia- 
logues are  no  small  part  of  our  birthright  in  English  literature. 

In  my  opinion,  however,  the  modern  zoologist  who  studies 
Berkeley  must  also  ask  whether  natural  selection,  so  far  as  it 
accounts  for  living  things  and  their  works  and  ways,  does  not, 
in  the  same  measure,  account  for  language ;  both  that  which  men 
use  among  themselves,  and  that  which  we  find  in  nature. 

The  teleologist  of  our  day  is  brought  face  to  face  with  the 
question.  What  if  we  should  some  time  find  that  we  know  no 
contrivances  and  no  contrivers,  except  those  that  are  part  of  the 
chain  of  natural  causation  .?  Unless  he  can  show  that  this  never 
can  be  proved,  by  proving  its  reverse,  is  it  not  clear  that  he  must 
abandon  his  search  for  intention,  or  seek  it  elsewhere  than  in 
the  contrivance  of  nature .'' 

Is  it  not,  when  all  is  said,  illogical  to  seek  a  supernatural  basis 


338  THE  FOUNDATIONS  OF  ZOOLOGY 

for  natural  theology?  If  we  are  to  find  a  basis  for  teleology 
anywhere,  must  we  not  seek  it  in  nature  rather  than  outside 
nature  ? 

No  one  supposes  that  the  scientific  study  of  philology,  and  the 
proof  that  the  life  and  growth  of  language  are  natural,  has  any 
bearing  upon  the  reality  or  the  value  of  language.  He  who  fears 
that  the  discovery  of  mechanical  explanations  of  the  order  of 
nature  would  destroy  the  proof  that  nature  is  a  language,  seems 
no  more  reasonable  than  one  who,  having  enjoyed  and  profited  by 
good  books,  should  assert  that  these  books  have  lost  their  use  and 
their  power  to  please  and  to  instruct,  through  the  discovery  that 
they  are  made  by  machinery  in  printing-offices. 

As  modern  zoologists  find  no  reason  to  believe  the  laws  of  their 
science  are  any  less  mechanical  than  those  of  physics  and  chem- 
istry, Agassiz's  conviction  that  natural  history  is  a  language  has 
failed  to  commend  itself  to  them  —  because  he  holds  it  essential  to 
assert  that  these  laws  are  fiothing  but  categories  of  thought,  and 
because  he  holds  that  things  physical  cannot  also  be  ideal. 

As  the  modern  man  of  science,  while  convinced  that  nature  is 
orderly,  does  not  know  whether  it  is  "arbitrary"  or  "necessary," 
he  has  failed  to  be  convinced  by  Berkeley,  who  holds  that,  since 
a  language  must  be  arbitrary  in  order  to  be  a  language,  none  who 
do  not  admit  that  nature  is  arbitrary  can  hold  it  to  be  a  language ; 
although  he  himself  asserts,  in  another  place,  that  it  is  necessary. 

It  is  no  new  thing  in  history  for  beliefs  to  suffer  because  their 
supporters  have  held  to  be  essential  certain  opinions  as  to  matters 
of  fact  which  have  proved  erroneous. 

"  Every  man  is  not  a  proper  Champion  for  Truth,  nor  fit  to 
take  up  the  Gauntlet  in  the  cause  of  Verity:  many,  from  the 
ignorance  of  these  maxims,  and  an  inconsiderate  Zeal  unto  Truth, 
have  too  rashly  charged  the  Troops  of  Error,  and  remain  as 
Trophies  unto  the  enemies  of  Truth.  A  man  may  be  in  as  just 
possession  of  Truth  as  of  a  City,  and  yet  be  forced  to  surrender."^ 

Science  tells  us  that  the  things  that  take  place  in  nature  are 
neither  less  nor  more  than  one  who  knows  the  data  has  every  rea- 
son to  expect.  With  this  the  work  of  science  ends ;  and  here  I 
must  end  my  work  on  the   Principles  of   Science ;   for  these  prin- 

^  Browne,  "  Religio  Medici,"  7. 


LOUIS  AGASSIZ  AND   GEORGE  BERKELEY  339 

ciples  fail  to  tell  us  why  the  things  we  expect  should  be  the  things 
that  come  about. 

The  question  why  the  things  we  expect  should  be  the  things 
that  come  about  is  the  one  that  concerns  the  natural  theologian  ; 
for  it  is  the  same  as  the  question,  What  is  the  Cause  of  Nature? 

To  this  all  must  seek  an  answer  for  themselves;  for  each  has 
at  his  command  all  the  data  within  the  reach  of  any  student  of 
science. 

As  for  myself,  I  hope,  with  all  my  getting,  to  get  understand- 
ing;  for  "the  heart  of  him  that  hath  understanding  secketh 
knowledge.  The  merchandise  of  it  is  better  than  the  merchan- 
dise of  silver,  and  the  gain  thereof  than  fine  gold.  She  is  more 
precious  than  rubies;  and  all  the  things  thou  canst  desire  are  not 
to  be  compared  unto  her.  Her  ways  are  ways  of  pleasantness, 
and  all  her  paths  are  peace. 


For  you  who  have,  at  this  time,  for  my  encouragement,  called  yourselves  my 
students,  I  have  written  this  book  which  has  been  my  own  so  long  that  I  should 
part  from  it  with  regret,  did  I  not  hope  that,  as  you  study  the  great  works  to  which 
I  have  directed  you,  you  may  still  call  me  teacher. 

I  have  treated  subjects  which  I  should  not  dare  to  handle  if  the  thoughts  were 
my  own ;  but  the  book  contains  little  which  you  will  not  find  far  better  presented  by 
abler  pens,  although  I  hope  that  the  words  of  one  whose  standpoint  is  tlie  same  as 
your  own  may  help  you  to  find  the  meaning  of  older  writers. 

If  you  are  indeed  my  students,  you  are  not  afraid  of  hard  work,  so  in  this  day  of 
light  literature,  when  even  learning  must  be  made  easy,  you  must  be  my  readers, 
and  you  must  do  double  duty ;  for  I  take  the  liberty  of  a  teaclier  with  his  pupils, 
and  ask  that,  after  you  have  read  the  book,  you  will  some  day  read  it  again ;  since 
I  hope  that  what  may  seem  obscure,  may,  on  review,  be  found  consistent  and 
intelligible. 

Brightside,  March  25, 1898. 


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